NATURAL SCIENCES OP PHILADELPHIA. 221 



spite of the difference in the number of the scales, especially those between 

 the back and lateral line * The colors of the two species are also different, 

 the present having a very distinct sulphur-yellow spot immediately behind 

 the dorsal fin, and extending obliquely forwards and downwards, as in C. 

 puncta. This character was inadvertently omitted in the original description. 



Notes on the LABROIDS of the Western Coast of North America. 

 BY THEODORE GILL. 



Within the short time that has elapsed since the publication of the descrip- 

 tions of the Labroids of Lower California, two most important works relating 

 wholly or in part to the Labroid alliance have been given to the world. Dr. 

 Bleeker, after having published in the Proceedings of the Zoological Society 

 of London,! an( i f those of the Royal Academy of Amsterdam,! an analytical 

 conspectus of the family of Labroids, in his great work on the Fishes of the 

 Indo-Molluccan Archipelago, has with great precision described and figured 

 the numerous species of those seas. Dr. Giinther has also issued the fourth 

 volume of his Catalogue in which he has introduced some slight modifications 

 in the generic arrangement formerly proposed by him, and has given diagnoses 

 of all the determinable species. 



The family of Labroids as understood by the writer has the limits assigned 

 to it by Bleeker, the families Scaroids and Siphonognathoids being apparently 

 valid. Giinther has embraced the three under one family, and has even re- 

 ferred the genus Siphonognathus to a "group," including in addition Odax, 

 Coridodax and Olistherops, considering the genera Odax and Siphonognathus 

 " as closely and naturally allied as Sus and Babirussa." Siphonognathus, how- 

 ever, disagrees with Giinther's diagnosis of the Labridse in having no " ventral 

 fins thoracic, with one spine and five soft rays," and instead of the " bran- 

 chiostegals five or six," only four. As I both believe that a genus should have 

 the chief characters of the family in which it is introduced views shared with 

 most naturalists and believe that those characters in which Siphonognathus 

 differs from the Labroids are important in this group of families, especially 

 when joined to such a modification of form as it presents, I eliminate from the 

 Labroids that genus formerly recognized as the type of a peculiar family by 

 myself and shortly afterwards by Bleeker. If two such dissimilar groups have 

 any analogies, I should say that Siphonognathus and Odax bear the same rela- 

 tion to each other as Sus and Hippopotamus types of distinct families. 



The generic distinctions of Dr. Bleeker seem to be in almost all cases happy, 

 and the subfamilies Cheiliniformes, Pseudolabriformes Pseudodaciformes, 

 (= Pscudocina Gthr.) Chelioniformes, Labriformes, (= Labrina Gthr.) Odaci- 

 formes and Clepticiformes appear to be natural, although concerning the fir3t 

 and fifth there may be some uncertainty. The other subfamilies Novaculae- 

 formes, Labrichthyiformes and Cossyphiformes appear to require revision. 



Dr. Giinther has enunciated for the first time a most interesting and import- 

 ant generalization for the Labroids which may also be extended to other 

 families. " In those genera which are composed entirely or for the greater 

 part of tropical species, the vertebral column is composed of twenty-four or 

 nearly twenty-four vertebrae, whilst those which are chiefly confined to the 

 temperate seas of the northern and southern hemisphere have that number in- 



* It is possible that the number of transverse rows of scales, and the longitudinal rows below 

 the lateral line, given in my former description, may be too high, and is at least doubtful, the 

 scales having been mostly rubbed off, and only ascertainable through the scars left by them. 



t Op. cit,, 1862, pp. 408118. 



% Verslagen en Mededeelingen der Koninklijke Akademie von Wetenschappen, Amsterdam, vol, 

 xiii. pp. 94109. 



1863.] 



