NATURAL SCIENCES OF PHILADELPHIA. 501 



Rhina japonica Gill = Squatina japonica Bleeker. 



Another species also nearly allied to the R. squatina is found along the east- 

 ern coast of the United States. 

 Rhina dumerili Gill = Squatina dumeril Les. 



A sixth has been described as an inhabitant of the California seas. 

 Rhina californica Ayres = Squatina californica ylyres, oliui. 



Tlie-name of a species (Squatina angelina Gray,) inhabiting the Caribbean sea 

 has been published in Gray's Catalogue of the Ckondropterygians, but not the 

 slightest diagnosis has been given. 



Rhina californica Ayres. 

 Squatina californica Ayres, Proc. of the California Academy of Natural Sci- 

 ences, part 2, p. 29, 1859. 

 Rhina californica Ayres, Proc. of the California Academy of Natural Sciences, 

 part 2, p. 54, fig. 7, 1861. 



On the limits and affinity of the Family of LEPTOSCOPOIDS. 

 BY THEODORE GILL. 



In the Proceedings of tlie Academy of Natural Sciences for April, 1859, 

 (vol. xi. p. 282,) there has been first made known a peculiar type (Dactylos- 

 copus tridigitatus) of fishes having the general appearance of a Uranoscopoid, 

 but distinguished by the structure of the ventral fins, each of which had 

 three simply articulated rays like those of the Blennioids. " Notwithstanding 

 the abnormal and blennioid structure of the ventrals," the new type was said 

 to agree in all other characters, except dentition and the origin of the dorsal 

 fin, with a species referred to the genus Uranoscopus* by Sir John Richardson ; 

 it was consequently referred next to that fish, but as the type of a distinct sub- 

 family, (Dactyloscopinse,) the species of Richardson being also considered as 

 the type of another peculiar subfamily, (Leptoscopinse.) 



In the " Annals and Magazine of Natural History," for February, I860, 

 (vol. iii. p. 86,) Gunther described a type which differed from Leptoscopus and 

 agreed with Dactyloscopus in the want of palatal teeth. 



In a subsequent " Synopsis of the Uranoscopoids, " published in the Proceed- 

 ings of the Academy for May, 1861, (vol. xiii. p. 108,) the correctness of the 

 approximation of the DactyloscopinaB next to Leptoscopinse was still further 

 insisted upon, and both were retained in the same family with the Uranosco- 

 pinae. 



In the third volume of the "Catalogue of the Acanthopterygian Fishes in 

 the Collection of the British Museum," Dactyloscopus was referred to the 

 Blennioids, and interposed between Tripterygium and Dictyosoma. Dr. Gun- 

 ther remarked, that "Dactyloscopus has been referred by Gill to the Uranos- 

 copina,\ from which, however, it differs in several cardinal characters. The 

 structure of the dorsal and ventral fins is that of a Blennioid. The absence 

 of pseudo-branchice is very peculiar ; but in this respect it differs equally from 

 the Uranoscopina and Blenniidae."J 



The Uranoscopinse formed a "group" or subfamily of the family of Trachi- 

 nidae as understood by Gunther. 



* Leptoscopus macropygus. 



f The group Uranoscopina of Gunther, which is equivalent to the family of Uranoscopoids, 

 after the elimination of the species with less than five ventral rays, is meant, and not the sub- 

 family of Uranoscopinae as restricted by Gill. 



J GUnther, op. cit., iii. p. 279. 



(S In his remarks on the family Blenniidae, Dr. Gunther has observed that the value of the 

 development of the pseudo-branchiae, as a character of that family, "appears not to be sufficient, 

 Dactyloscopus and PaUzcus forming exceptions, although the structure of their dorsal fin proves 

 that their natural place is with or near the Blennioids." The real structure of the dorsal of Dactylos- 

 copus proves the contrary ; the natural place of Patacus is rather near, than with, the Blennioids. 

 (Genypterusis a Chilian Ophidioid; Loarces and Lycodes form a peculiar family, all wanting true 

 dorsal spines.) 



1862.] 



