ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 53 



In connection with the eyes there is a specific dense organ in the 

 form of a vesicle filled with rounded cells, containing a highly refractive 

 nucleus of irregular form ; the nerve which supplies this organ does not 

 arise directly from the brain, but from the optic nerve about midway 

 between the eye and the nerve-centre. Hydrodroma dispar has four of 

 these organs, which lie in the depressions at the four angles of the dorsal 

 shield. The direct connection of this organ with the optic nerve leads 

 to the supposition that we have here to do with the vestiges of eyes. 



After a short notice of the musculature, the author passes to the 

 generative organs, as to which he has nothing essentially new to add 

 to the descriptions given by Croneberg ; a somewhat detailed description 

 is, however, given. 



€. Crustacea. 5 



Male Copulatory Organs on first Abdominal Appendage of some 

 female Crayfishes.* — Herr D. Beyendal directs attention to some abnor- 

 malities in the appendages of the first abdominal segment of female 

 crayfishes. He has observed that these appendages vary much in form ; 

 sometimes they were quite absent, some were spoon-shaped, and in a few 

 they presented the characters of the male ; the last were otherwise quite 

 normally constituted females. The male appearance does not, therefore, 

 seem to be any indication of hermaphroditism, nor is it a sign of a return 

 to an earlier hermaphrodite stage. We have, in fine, to do rather with 

 a well-marked case of the variations which are exhibited by useless 

 vestigial organs. The cause of the possession of male organs is to be 

 sought for in the influence of inheritance from its male j)arent by the 

 female. 



Indian AmpMpoda.f — Mr. G. M. Giles, continuing his notes on the 

 voyage of H.M.S. ' Investigator,' calls attention to the fact that he has 

 as yet found only two species of Amphipods previously known. Since 

 his last publication Mr. Giles has found eleven new species. A blind 

 Anonyx which appears to feed on drift, an Ampelisca, a Microdeutopus, 

 and a Monoculodes are described. An interesting form, which the dis- 

 coverer calls Goncholestes dentaUi g. et sp. n., was found forming a distinct 

 tube within Dentalium shells. Next comes a careful description, with 

 seven figures, of AmpMthoe indica Milne-Edwards. New species of 

 Atylus, Urothoe, Caprella are recorded, diagnosed, and beautifully illus- 

 trated. Another form, which belongs to the family Platyscelidae, will fit 

 into no existing genus, and is named Elsia indica g. et sp. n. 



New Family of Commensal Copepods4 — M. E. Canu gives a note 

 on the Hersiliidae, a new family of commensal Copepods, which must be 

 regarded as distinct from the Siphonostomata and the Peltidiidfe. The 

 body is completely segmented, and the first thoracic somite is united 

 with the cephalic ring; the anterior antennae have seven joints, and are 

 similar in the two sexes ; the posterior antennae are simple and have four 

 joints. The mandibles have no palps nor any masticatory teeth ; at their 

 distal extremity they are provided with mobile accessory seizing pieces, 

 and flattened plates, the edge of which may be denticulated or carry 



* Bihang Handl. K. Svensk. Vet. Akad., xiv. (1888) iv. No. 3, 35 pp (1 pi ) 

 and Oefvers. af Forhandl. K. Svensk. Vet. Akad., 1888, No. 5, pp. 343-6. 

 t Journ. Asiat. Soc. Bang., Ivii. (1888) pp. 220-55 (7 pis.). 

 X Comptes Eendus, evil. (1888) pp. 792-3. 



