On the Anatomy of Prosthecocotyle torulosa (Linstow) and Prosthecocotyle heteroclita (Dies.)

Abstract

In the Report on the Entozoa collected by H.M.S. “Challenger” Dr O. von Linstow described two new tapeworms, which he named Tetrabothrium torulosum and T. auriculatum. The resemblance of the head of T. auriculatum with that of Prosthecocotyle Forsteri described by Monticelli seemed to me to indicate that the Tetrabothrium described by Linstow probably belonged to the genus Prosthecocotyle.Through the kindness of Sir John Murray, I received from the British Museum the original specimens for inspection, for which I wish to express here my warmest thanks. The following lines give the results of my examination; but before entering upon the description, let me say something on the systematic position of these two animals. As I have already remarked, Prof. Monticelli has rightly erected a new genus named Prosthecocotyle for the tapeworm Tœnia Forsteri, Krefft. To this genus belongs, besides P. Forsteri, other parasites of birds which have been placed in the genera Tœnia, Tetrabothrium, Amphoterocotyle, Bothridiotœnia, Bothriocephalus. According to my researches the following species belong to the genus Prosthecocotyle:—1. P. Forsteri (Krefft), (syn. Tœnia Forsteri, Krefft), from Delphinus Forsteri (Gray) and Delphinus delphinus, L.2. P. Monticellii, Fuhrmann (syn. Tœnia erostris, ex parte, Bothridiotœnia erostris, var. minor, Lönnberg), from Fulmarus glacialis, L.3. P. umbrella, Fuhrmann, from Diomedea sp. (?).4. P. torulosa (Linstow), (syn. Tetrabothrium torulosum, Linstow), from Diomedea brachyura, Temm.