Palaemon Serratus Research Articles

AN ELECTRON MICROSCOPE STUDY OF SOME CYTOPLASMIC INCLUSIONS OF THE NEURONES OF THE PRAWN, LEANDER SERRATUS

SYNOPSISNeurones from the thoracic and abdominal ganglia of the prawn, Leander serratus, were studied by optical and electron microscopy. The following cytoplasmic inclusions have been studied:1. The endoplasmic reticulum, which is more or less uniformly distributed throughout the cytoplasm in a vesicular form. Parallel lamellæ associated with granules have rarely been encountered. Sufficiently large aggregates of organized endoplasmic reticulum, corresponding to the Nissl bodies of vertebrates, have not been seen.2. The “dictyosomes”, which are composed of stacks of paired non‐granular membranes. The stacks are generally seen as rods, crescents, and horse‐shoes in electron micrographs, and resemble the complex known generally as the “Golgi apparatus”. The evidence indicates that these lamellar structures correspond to the spherical or nearly spherical bodies that are seen in living cells and colour with neutral red.3. The “trophospongium”, which is shown to consist of branching invaginations of the cell membrane, containing processes from the glial cells. It ramifies in the form of long, thin, branching filaments throughout the cytoplasm. Some workers with the light microscope have mistaken these branching invaginations for mitochondria.4. The mitochondria, which are mostly short. Long, filamentous mitochondria which might be expected to give the appearance of the “trophospongium” have not been encountered.

The Cytoplasmic Inclusions of the Neurones of Crustacea

ABSTRACT Those who have studied the neurones of Crustacea have given very- divergent accounts of the ‘Golgi apparatus’ of these cells. Poluszynski (1911) described only short, straight or slightly sickle-shaped threads; he considered them as the Golgi apparatus. Monti (1915) believed that the Golgi apparatus of this cell was constituted by the mitochondria. She thought that they were long, wavy threads, which were blackened by the Golgi methods and formed a reticulum of the type seen in the neurone of vertebrates. Ross (1922) described a framework of ‘trophospongium’ connected with the surface of the cell. He thought this was additional to a reticular ‘Golgi apparatus’.

Extraction and Purification of ‘Queen Substance’ from Queen Bees

QUEEN honeybees (Apis mellifera) secrete material which, distributed through the colony, affects the bees in two ways, inhibiting the development of ovaries in workers and influencing their behaviour by inhibiting queen rearing (that is, queen-cell construction)1. Carlisle and Butler2 observed similarities between the ‘queen substance’ of honeybees in the form of an alcoholic extract and the ovary-inhibiting hormone of prawns (Leander serratus), and it is a justifiable extrapolation to suppose that this material has important physiological effects on animals of other phyla.

Moulting hormones in Palaemon (=Leander) (Crustacea Decapoda) II. Differences between populations

Eye-stalk removal in certain species of Brachyura and Astacura has almost invariably led to the initiation of proecdysis. In other decapod crustaceans, however, there have been significant variations in the results of this operation. Thus Travis (1951) found that eye-stalk ablation had no effect on the duration of the moult cycle in Panulirus argus. And in the Natantia, even in a single species, quite different results have been reported. Drach (1944) found that eye-stalk removal in Palaemon (=Leander) serratus (Pennant) led, as in crabs, to the initiation of proecdysis and to accelerated moulting. In ignorance of this work I repeated some of the same experiments and found that eye-stalk removal in P. serratus led to slower moulting (Carlisle, 1953 a)— a result quite opposite to that of Drach. Scheer & Scheer (1954) confirm my results in the same species.

On the sexual biology of Pandalus borealis (Crustacea Decapoda) I. Histology of incretory elements

Anatomical and histological details are here given of two organ systems, which, my experiments lead me to believe, may secrete hormones concerned in the sex reversal that overtakes all male Pandalus borealis Kroyer. The descriptions eschew any attempt at detailed cytology, and refer exclusively to prawns taken from the population of Gullmarf jord in south-west Sweden. There is reason to believe that, as with Palaemon (= Leander) serratus (cf. Carlisle, 1955), different populations may vary widely in the detailed topography of the endocrine organs, as well as in appearance, life history and growth rate (cf. Horsted & Smidt, 1956).

Some Observations on the Occurrence of Leander serratus Pennant, in Irish Waters

Some Observations on the Occurrence of Leander serratus Pennant, in Irish Waters

The Modes of Action of Toxic Agents III. Mercuric Chloride and N-Amylmercuric Chloride on Crustaceans

Experiments have been carried out with 203Hg-labelled n-amylmercuric chloride (n-C5H11HgCl) and mercuric chloride (HgCl2) to study the modes of action of these compounds as poisons to some crustaceans.Differences between the susceptibilities of Artemia salina and Elminius modestus to the poisons do not reflect differences between the quantities of these compounds which the animals can tolerate in their tissues, but are directly related to the rates at which the poisons are accumulated. Thus, experiments with either species have shown that Hg is taken up at approximately the same rate from equitoxic solutions of the two poisons; and the rates at which Hg is accumulated by the two species from equitoxic solutions of either poison are of the same order.Experiments with reduced glutathione have given results consistent with the view that most of the Hg taken up by either species penetrates into the tissues of the test animals and does not act simply by becoming attached to their surfaces.Direct evidence of the penetration of Hg compounds into a crustacean has been obtained from experiments with Leander serratus. Considerable amounts of Hg have been detected in the antennary glands.

The Influence of Pigment Migration on Vision of Higher Crustacea

ABSTRACT Exner believed that the movement of the distal pigment during light-adaptation improved the visual acuity of the superposition eye. This hypothesis was tested by measurement of the visual acuity of Leander serratus, Pandalus montagui and Praunus flexuosus under different conditions. When a dark-adapted animal is placed in the light the proximal pigment migrates into the light-adapted position more rapidly than the distal pigment. The distal pigment, but not the proximal pigment, undergoes diurnal rhythm and tends to migrate into the dark-adapted position at night, even when the animal is illuminated. The visual acuity may therefore be tested when the distal pigment is still in the dark-adapted position and the proximal pigment in the light-adapted position. No difference in visual acuity could be detected as a result of changes in the position of the distal pigment. Visual acuity increases and light sensitivity decreases when the dark proximal pigment migrates over the reflecting (tapetal) layer. Eupagurus bemhardus, which lacks the typical tapetum, shows no detectable change in visual acuity or sensitivity after being kept in the dark. These experiments do not support Exner’s view of the function of the distal pigment. They indicate that visual acuity is improved by the presence of the dark proximal pigment at the base of the proximal retinulae, probably because this pigment reduces stray reflexions from the back of the eye (halation). It is suggested that since the crystalline cones and crystalline tracts form optically continuous strands with a higher refractive index than that of the surrounding medium they may act as wave guides. If so they would retain light entering the corneal surface from sources close to the axis of the ommatidium, and so concentrate it on the rhabdomes and adjacent retinulae.

ENDOCRINE CONTROL IN THE CRUSTACEA

ENDOCRINE CONTROL IN THE CRUSTACEA

Receptor elements in the muscles ofLeander serratus

In continuation of the studies on receptor elements in the Crustacea the common prawn,Leander serratus, has been investigated by the methylene-blue method applied in the same way as described in an earlier publication (Alexandrowicz, 1951). It has been found that there are inLeanderreceptors of the same kind as in those crustaceans previously investigated, some of which exhibit features not yet observed before. As in other crustaceans they are similarly situated on the dorsal side of the body, but since a knowledge of the disposition of the dorsal muscles in the thorax and the abdomen is necessary for locating them, some data about the topography of the muscles are first given.

Local variations in the colour pattern of the prawn Leander serratus (Pennant)

During investigations into the endocrinology of Leander ( =Palaemon) serratus (Pennant) several differences in physiology (which will be reported in this Journal at a later date) have been found between the prawns from Plymouth and those from Roscoff on the north coast of France. These experiments involved the repeated handling and the close examination of about a thousand prawns from Roscoff and many more from Plymouth. Increasing familiarity with these animals led to the realization that the two samples could readily be distinguished by eye. It was not always possible to determine the provenance of a single individual in this way, but any group of five or six could be told at a glance. A detailed examination of the external morphology showed that the characteristic differences by which the provenance of these animals could be determined lay not in any anatomical feature but in the disposition and arrangement of the chromatophores which form the pattern on the dorsal side of the cephalothoracic shield and the anterior part of the abdomen. Great individual variations were to be seen, but differing trends of development of the patterns were found in the two populations. There was some degree of overlap between the populations, but only about 15% of the prawns lay in this region of overlap and thus failed to bear the marks of their locality; the remaining 85% could be assigned to either Roscoff or Plymouth with little difficulty. Recently I have been able to examine about forty prawns from Concarneau, on the Atlantic coast of France, and these again are mostly different from either of the other two samples.

Relation of Colour Change to Moulting in Prawns

STUDIES of crustacean hormones have heretofore been concentrated either on chromatophorotropic actions, or upon effects on moulting and related metabolic phenomena. We have now obtained evidence that, in Leander serratus (Pennant), the chromatophorotropic hormones are also concerned in the intermoult cycle. Numerous previous studies have shown that eyestalk removal accelerates moulting in many species of crustaceans, including L. serratus 1. We found that, in a series of 114 eyestalkless animals, only two moulted, while of 146 normal animals kept under identical conditions, twelve moulted. This difference is statistically significant at the 5 per cent level of probability. We are unable to account for the difference from Drach's results1; but Carlisle (personal communication) has suggested that there are important racial differences between prawns of the same species at Naples, Roscoff and Plymouth. Analysis of the effect of removal of eyestalk showed that it could be attributed to an increase in length of stage D 2 of the intermoult cycle2, during which the old integument is undergoing resorption, and the new integument is being formed, and to an increased mortality immediately preceding the moult in eyestalkless specimens.

Moulting Hormones In Leander (Crustacea Decapoda)

Removal of the eyestalks in Leander serratus does not result in an earlier moult, a shorter intermoult period, or a higher moult rate. There is no evidence of an eyestalk moult-inhibiting hormone in this species. The evidence points to the existence of an eyestalk moult-accelerating hormone. The possible correlation of the presence of the moult-inhibiting hormone and seasonal moulting is discussed.

Neurosecretory pathways in the prawn, Leander serratus.

LAST year, I reported the presence of neurosecretory cells within the tritocerebral commissure of Penaeus braziliensis, and the distribution of fuchsinophil droplets along the course of two post-commissure nerves1. Two flat extensions of these nerves, adjoining blood sinuses and therefore described as sinus-plates, were full of these droplets. Injection experiments showed that those regions with the most droplets yielded the most potent extracts when these were tested by their effects on the white chromatophores. The sinus-plates resemble the sinus-glands of the Mysidacea2, and this parallel has been made more striking by the recent evidence of Enami3, Passano4 and others that the sinus-glands of some decapods are supplied by neurosecretory cells in the medulla terminalis; the secretory products pass along nerves and are released via secretory canals in the sinus-glands2. In the present experiments a search was made for secretory canals in the tritocerebral commissure and the post-commissure nerves of the prawn, Leander serratus. The nervous system was stained by a modification of the methylene blue method used by Alexandrowicz5; specimens were immersed in a solution of methylene blue for nine hours in a refrigerator.

The biology of the common prawn,Leander serratusPennant

This work was undertaken at the suggestion of Mr F. S. Russell that little was known about the natural history of even so familiar a species asLeander serratus, the common prawn of the English Channel, which may at times form a valuable natural resource to the inshore fishermen. Attention was therefore chiefly concentrated on its growth rate and breeding biology. In spite of the long breeding season the statistical method of studying growth was adopted when preliminary results appeared successful. By this method additional data could be obtained on distribution and migration. In the closely related genusCrangon, growth has been shown to be retarded under laboratory conditions (Nouvel & van Rysselberge, 1937), so that an experimental study could not be relied on to give a picture of the normal life history. Höglund's recent monograph (1943) has treatedLeander squillain great detail. However, this species differs considerably in size and distribution fromL. serratus, and it was felt that a similar study in the Plymouth area would not be mere repetition; in fact the biology ofL. squillaitself differs somewhat in the two districts.

The control of retinal pigment migration in Leander serratus.

1. The distal and the proximal retinal pigments of Leander serratus can alter their positions in response to light and darkness. 2. The reflecting pigment shows a great movement at night which persists as a diurnal rhythm in continued darkness, but during the day it is unaffected by change of illumination. 3. The extent of distal pigment migration depends on the shade of the background on which the animal is placed, if the intensity of incident illumination is constant. 4. In constant darkness the proximal pigment continues to migrate diurnally for some days, at least. At midnight it shows a greater degree of dark-adaption than it does during the day; the distal pigment cells do not exhibit any detectable persisting diurnal rhythm in continued darkness. 5. After removal of the sinus-gland the distal pigment, in most of the operated animals, attained the position of maximal dark-adaption and was unaffected by change of illumination; it therefore appears not to respond directly to illumination. On the other hand, the proximal pigment in animals without sinus glands exhibited the same responses to change of illumination as those observed in normal animals. 6. In a series of experiments one eye of an animal was covered and the other eye was illuminated. In all the experimental animals so treated the proximal pigment of the exposed eye became light-adapted, but that of the covered eye attained the position of dark-adaptation observed in animals kept in darkness during the day. 7. A slight difference between the position of the distal pigment in the exposed eye and the covered eye of an individual could sometimes be observed; the difference was most striking in those animals which were on a black background, and in those animals which were placed in a light-proof box (in darkness) with one eye protruding through the box to be illuminated. 8. The distal retinal pigment of Leander serratus does not respond directly to illumination when the sinus gland is absent, yet in normal animals direct illumination enhances the light adaptation of the distal pigment; possibly illumination sensitizes the distal pigment cells to the hormone by which they are activated. The migration of the proximal pigment under illumination appears to be independent of the sinus gland. The influence of direct illumination on the proximal pigments appears to be great.

Osmotic relations of some metazoan parasites

1. The osmotic behaviour of three parasites in normal and experimental media has been studied with a view to understanding the relationship with their hosts.2. Angusticaecum sp., a nematode frpm the intestine of the tortoise, is hypertonic in media of very low concentrations (1·1–1·3 % NaCl in tap water), but becomes isotonic in sea water and slightly hypertonic in 50 % sea water. Ligaturing experiments show that its cuticle is permeable to water and probably to salts.3. Lernaeocera branchialis, a blood-feeding copepod from Gadus spp., is hypotonic to the surrounding sea water so long as it remains attached to its host, its blood showing an osmotic pressure equivalent to 2·O–2·8 % NaCl. Isotonicity with the medium is established when the parasite is excised and kept alive. Hypotonicity of Lernaeocera is probably caused by the low osmotic pressure of the blood of its host (1·443 % NaCl in Gadus pollachius), to which it is permanently attached.4. Bopyrus squillarum, a blood-sucking isopod from Leander serratus, is isotonic or slightly hypotonic to sea water, the tendency towards hypotonicity being probably the result of the hypotonic nature of the blood of the host.5. The osmotic properties of Lerpaeocera and Bopyrus would suggest their ability to survive in dilute sea water, a fact which is supported by their occurrence on hosts living in inshore or estuarine habitats.

Osmotic Properties of the Common Prawn

IN a previous communication1 I referred to the homoiosmotic behaviour of Palœmonetes varians and its ability to maintain hypotonicity in normal sea water. Further experiments on the osmo-regulatory mechanism of some Crustacea have revealed that the common prawn, Leander serratus (Pennant), is also definitely hypotonic when in normal sea water.

14. The Larval Development of some British Prawns (Palæmonnidæ).‐I. Palæmonetes varians.*

Proceedings of the Zoological Society of LondonVolume 94, Issue 1 p. 297-328 14. The Larval Development of some British Prawns (Palæmonnidæ).-I. Palæmonetes varians.* Robert Gurney M.A., F.Z.S., Robert Gurney M.A., F.Z.S.Search for more papers by this author Robert Gurney M.A., F.Z.S., Robert Gurney M.A., F.Z.S.Search for more papers by this author First published: March 1924 https://doi.org/10.1111/j.1096-3642.1924.tb01503.xCitations: 12 † *M. E. Sollaud's work on the larval development of the Palæmoninæ (Bull. Biol. France et Belgique, Ivii. 1923, p. 509) contains an excellent account of the development of Palœmonetes varians and also of Leander serratus. Unfortunately, my own description was already in print when I received from M. Sollaud a separate copy of his paper. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume94, Issue1March 1924Pages 297-328 RelatedInformation

IX. On correlation of certain external parts of Palœmon serratus

In 1890 Professor Weldon published (‘ Roy. Soc. Proc.,’ vol. 47, p. 445) the results of measurements of certain organs of the common shrimp, with a view to establish by accurate data the degree of variation existing in those organs. In a later paper (‘Roy. Soc. Proc.,’ vol. 51, p. 2) he determined, by Mr. Galton’s method there described, the degree of correlation existing between four organs of the same animal, and in a recent paper (‘Roy. Soc. Proe.,’ vol. 54, p. 318) similar determinations have been worked out by him for certain organs of Carcinus mœnas . Some time ago it was suggested to me by Professor Weldon that I should determine the values of correlated variations in a number of parts of the hard exoskeleton of the common prawn ( Palœmon serratus ). Accordingly, 1000 adult female prawns, chosen at random, were procured from Plymouth and measured. Twenty-two measurements were made of each prawn, except in the case of two or three measurements which were made on part only of the sample.