Scorpion Genus Research Articles

The Taxonomy of the False Scorpion Genus Synsphyronus with Remarks on the Sporadic Loss of Stability in Generally Constant Morphological Characters (Arachnida: Chelonethida)

The genus Synsphyronus Chamberlin was erected in 1930 (Ann. and Mag. Nat. Hist. (10), 5 : 609, 616–617) to accommodate an unusual species of the family Garypidae which differed primarily from other members of the group in having the metatarsus and tarsus of the legs secondarily fused to form a typical miotarsus. At the time, it was pointed out that, in spite of this unusual character, the genus was undoubtedly truly referable to the family Garypidae on the basis of every other morphological character definitive of that group. In spite of this, Beier in 1932 (Das Tierreich, 57 :238) elevated the genus to family rank (Synsphyronidae) and removed it from the superfamily Garypoidea[2][1] to the Feaelloidea. Consideration of the following tabular summary of the normal characteristics of these two superfamilies will clearly reveal the untenability of Beier's disposition of this genus. In every character but the invariable presence of a normal, two-segmented tarsus, Synsphyronus agrees with the characters itemized under the heading Garypoidea. [1]: #fn-1

OOGENESIS OF LITHOBIUS FORFICATUS

Summary.1. The nucleolus of the oocyte nucleus is at first basiphil, then amphophil and finally completely acidophil showing prominent vacuoles. It discharges into the nucleus deeply basiphil circular and irregular masses of a chromatin‐like substance. The former remain in the nucleus and form secondary nucleoli which, becoming acidophil, ultimately disappear. The irregular masses, the nucleolar extrusions, are first plastered round the nuclear membrane where they bud off small pieces in the cytoplasm. Later they are detached from the nuclear membrane and lie in the cytoplasm where they become amphophil and then acidophil. As a rule they disappear before the vitelline yolk puts in its appearance.2. Strong evidence has been adduced by a comparative study of the various genera of scorpions with and without yolk in the oocytes in favour of the view that nucleolar extrusions are probably concerned in yolk formation.3. The Golgi apparatus in young oocytes consists of small rods collected in a patch on one side of the nucleus. Evidence, both direct and indirect, has been adduced in favour of the view that Golgi rods are transformed into fatty yolk. The Golgi rods, therefore, have a nutritive function in the oocyte of Lithobius.4. The fatty yolk is blackened even by chrome‐osmium, indicating the presence of free unsaturated fat in its constitution. The true vitelline yolk appears a considerable time after the fatty yolk and goes yellowish brown in osmic acid.5. In a centrifuged egg fixed by prolonged osmic acid method the fatty yolk forms a black band at one pole, whereas the vitelline yolk is thrown down at the other pole. The middle area of the egg consists of the mitochondria, the nucleus and the unchanged Golgi rods whose amount is, roughly speaking, inversely proportional to that of the fatty yolk.

V.—Descriptions of two new genera of scorpions, with notes upon some Species of Palamnæus

V.—<i>Descriptions of two new genera of scorpions, with notes upon some Species of</i> Palamnæus

XXXVIII.—Description of a new genus and species of Scorpion belonging to the group Jurini

XXXVIII.—<i>Description of a new genus and species of Scorpion belonging to the group</i> Jurini