474 Fart III. — Twentieth Annual Report 



recently Giesbreclit* have described as the male of Gancerilla. There is 

 in some respects a similarity in the structure of Caligidium with that of 

 Gancerilla, but I am not sure that the relationship between the two has 

 been fully established. Dr. Edward Graeffe in his fauna of the Gulf 

 of Trieste retains Caligidium vagahundum, Claus, under its distinctive 

 name, without any reference to its sexual relationship with Gancerilla. t 



Herpyllobiid^. 



Salenskya tuherosa, Giard and Bonnier. PI. XXV., figs. 17-22. 



1895. Saletiskya tuherosa, Giard and Bonnier, Contrib. a I'etude 

 des Epicarides ; Bull. Scient., vol. xxv., p. 472, pl. xiii. 



A few specimens of this remarkable form were found fixed between the 

 thoracic \e^s of Ainpelisca spinipes, Boeck, dredged near North Craig, 

 Firth of Forth, on July 7th, 1901. They agree very closely with the 

 figure of Giard and Bonnier, who obtained a single female and three 

 " pygmy males " on a specimen of the same amphipod from Le Croisie. 



The female (fig. 17) measures about "84 mm. (3^,- of an inch) in length, 

 and it is about as broad as long ; one or two of the females carried two 

 globular ovisacs, each one being nearly as large as the copepod itself. 

 No appendages are present. 



What seem at first sight to be the males, but, as Hansen has shown 

 (Choniostomatidse, p. 19), are really the larvae — the adult males being 

 degenerate like the females— (fig. 18) measure about '15 mm. ( j^ of an 

 inch). The anterior segment of the body is comparatively greatly dilated, 

 the remaining segments are small. The antennules are very short, and 

 three (or four) jointed, and furnished with two terminal setae and a club- 

 shaped appendage represented in the figure (fig. 19). Two pairs of limbs 

 which represent the first and second maxillipeds are shown in figures 12 

 and 13. 



My son, when dissecting the larvae, was able to make out two pairs of 

 thoracic feet ; each foot appeared to be composed of a two-jointed basal 

 part and a single one-jointed branch, which was armed with two small 

 spines on the exterior margin, and four plumose on the inner margin and 

 apex. 



This description will be found to differ (possibly by reason of age) 

 from the character shown by Giard and Bonnier, and my figures show a 

 further difference in a greater segmentation of the hinder part of the 

 abdomen. 



It is very probable that the parasite is congeneric, and quite possible 

 that it is identical with BJiiwrbina ampUsccB, Hansen, described from 

 Ampelisca hevigafa, Lilljeborg, by Hansen, in 1892 (Entomol. Med- 

 delelser, ii., pp. 207-234, pl. iii.), a memoir which I have not yet been 

 able to consult. J 



Order OSTRACODA. 



A considerable number of Ostracoda have been observed in the dredged 

 material examined during the year, but as they apparently all belong to 

 described species which for the most part are more or less generally dis- 

 tributed, I will only refer to the two following which appear to be some- 

 what rare. 



* Fauna u. Flora d. Golfes u. Neapel, vol. xxv., Astrocheriden, pp. 95 and 112, pl. x. 

 figs. 1-11. 



+ Fauna d. Golfes v. Triest, Arbeit, d Zooloq. Institute zu Wien, t. xiii., haft 1, p. 43 

 (1900). 



_ X I desire to express my indebtedness to Prof. D' Arcy W. Thompson for the identifica- 

 tion of this interesting crustacean, as well as for other information concerning it. 



