NOTES AND LITERATURE. 



ZOOLOGY. 



Notes on Recent Fish Literature.— In the Transactions of the 

 Liverpool Biological Society (XVII, 1903) Mr. Walter M. Tattersall 

 takes up again the classification of the lancelets in connection with 

 the study of Professor Herdman's collection from Ceylon. 



Tattersall recognizes about 12 species, with two or three marked 



toma and Asymmetron. As a synonym of Asymmetron (1893) he 

 places Epigonichthys (1876). The last mentioned name has of 



genera " Tattersall proposes to " abolish altogether " because most 

 of those proposed contain but a single species ; an inadequate reason 

 for those who mark divergence of character rather than number of 

 species, by the use of subgeneric names. Mr. Tattersall regards the 

 American B. caribceum as identical with B. lanceolatmn of Europe, 



usually smaller number of post-anal muscular impressions in the 

 American form (9 or 10 instead of 10, 11, 12 or 13). The Japanese 

 Lancelet (B.japonicum =B. nakagawce) is the same as the Ceylon 

 species, B. belcheri, and that again is indistinguishable from the 

 European. It has 63 or 64 .tiuscular impressions while B. lanceola- 

 turn has 60 to 63 and B. caribceum 58 to 61. The averages of 



in Asiatic specimens, a slight decrease in American. 



Tattersall rejects the genus Amphioxides, hziS^A on A. pelagicus 

 and characterized by the absence of oral cirri "because the absence 

 of oral cirri is no doubt a result of its pelagic life." But if pelagic 

 life brings about such important structural modifications, a matter by 

 no means proved, this is no reason why we should not regard these 

 modifications as of generic value. If Amphioxides is really without 

 cirri, as is probably the case, it is surely a valid genus. 



Mr. Tattersall states that "Jordan and Snyder consider B. naka- 

 gawce a new species solely on account of its geographical distribution." 

 In this he seems to miss the point. B. belcheri was described from 

 Borneo in very unsatisfactory fashion. The Japanese lancelet showed 



