24 REV, T, E. E. STEBBING— BISCATAN PLANKTON: 



6. SciNA CRASSicoRNis (J. C. Fabricius). 



1775. Astacus crassicomis, Fabricius, Systema Eatomologise, p. 415. 

 1793. Astacus crassicomis, Fabricius, Entomologia Systematica, p. 481. 

 1793. Cancer {Gammarelliis) crassicomis, Herbst, Krabben und Krebse, Bd. ii. p. 134. 

 1830. Hijperia corniyera, M.-Edwards, Ann. Sci. Nat. vol. xx. p. 387. 

 1840. Tyro cornigera, M.-Edwards, Hist. Nat. Crust, vol. iii. p. 80. 

 1853. Clydonia gracilis, Dana, U.S. Expl. Exp. vol. xiii. p. 834, pi. 55. fig. 6 a, h. 

 1885. Tyro atlantica, Bovallius, Bihang t. K. Sv. Vet.-Akad. Handl. Bd. x. No. 14, p. 14. 

 1885. Tyro Sarsii, Bovallius, Bihang t. K. Sv. Vet.-Akad. Handl. Bd. x. No. 14, p. 15. 

 1887. Tyro Sarsi, Bovallius, K. Sv. Vet.-Akad. Handl. Bd. xxi. No. 5, p. 9, pi. 1. figs. 1-17, 

 pi. 2. figs. 1-10. 



1887. Tijro atlantica, Bovallius, K. Sv. Vet.-Akad. Handl. Bd. xxi. No. 5, p. 13, pi. 2. figs. 11-18. 



1888. Scina cornigera, Stebbing, 'Challenger' Amphipoda, Reports, vol. xxix. p. 1273, pi. 146. 



1895. Scina cornigera, Stebbing, Trans. Zool. Soc. London, vol. xiii. pt. 10, p. 351. 



1896. Scina Edwardsi, Garbowski, Denkschr. k. Akad. Wien, Bd. Ixiii. p. 103 {&7), pi. 1. fig. 2, 



pi. 3. figs. 19-33, pis. 4-7, pi. 8. figs. 97-109. 



1900. Scina cornigera, Chevreux, Amphipodes de I'Hirondelle, p. 121. 



1901. Scina Edwardsi, Vosseler, Die Amphipoden der Plankton-Exp. p. 103. 



Additional references might be given, but the above will suffice to explain the 

 synonymy of this species. When describing it as Scina cornigera in 1888, I considered 

 that Dana's Clydonia gracilis could not be distinguished from it, and with this opinion 

 Dr. Vosseler, the latest writer on the group, agrees. In 1895 I called attention to the 

 probable identity of Tyro Sarsii, Bovallius, and this conclusion, which is accepted by 

 my friend M. Ed. Chevreux, was independently arrived at by Dr. Garbowski in 1896. 

 The last-named author, in his elaborate treatise on the Scinidse, also forcibly argues 

 that ^S*. atlantica (Bovallius) is a further synonym. But he thinks it advantageous to 

 discard both the names {atlantica and Sarsii) given by Bovallius, and to establish in 

 place of them " Scina Edwardsi, n. sp." This designation is accepted by Dr. Vosseler, 

 who to " Scina Edwardsi, Garbowski," allots no less than five earlier synonyms, since, 

 besides those already mentioned, beginning with the cornigera of Milne-Edwards, he 

 includes the longipes of Dana. The inclusion of this last must be regarded as extremely 

 hazardous, but all the rest appear to take legitimate precedence of the name Edwardsi. 

 There is, however, a name earlier than any of them, which ought not to be neglected. 

 This is the crassicomis of J. C. Eabricius, a name probably adopted from the manuscript 

 title of Cancer crassicomis, painted by Sydney Parkinson in 1768, of which the 

 drawing, still unpublished, is preserved in the Natural History Museum. Formerly I 

 thought that the description by Fabricius was not sufficiently definite to justify the 

 maintenance of his specific designation, of which the priority was otherwise beyond 

 dispute. Now, however, it appears from the synoptic table of all the known species 

 that there is really only one which adequately satisfies the conditions of the earliest 

 description. There are only three out of the fourteen which have the anterior antennae 

 longer than the body. But of these Scina stenopus has the first antennae not " crassi- 

 usculce," but remarkably slender, and Scina cedicarpus is an animal so small that the 

 carination of the back if existent could scarcely have been noticed in the eighteenth 



