47 Gobioidei, Discocephali, and Tasniosomi 



its living congeners, as might be expected if the smallness of 

 the adhesive disk is taken into account." 



Concerning the relations of the Discocephali Dr. Gill has 

 the following pertinent remarks: 



"The family of Scomberoides was constituted by Cuvier for 

 certain forms of known organization, among which were fishes 

 evidently related to Caranx, but which had free dorsal spines. 

 Dr. Giinther conceived the idea of disintegrating this family 

 because, inter alias, the typical Scomberoides (family Scombridcs} 

 have more than 24 vertebras and others (family Carangida] 

 had just 24. The assumption of Cuvier as to the relationship of 

 Elacate (Rachycentrori) was repeated, but inasmuch as it had ' more 

 than 24 vertebrae' (it had 25 = 12 + 13) it was severed from 

 the free-spined Carangida and associated with the Scombrida. 

 Elacate has an elongated body, flattened head, and a longi- 

 tudinal lateral band; therefore Echeneis was considered to be 

 next allied to Elacate and to belong to the same family. The 

 very numerous differences in structure between the two were 

 entirely ignored, and the reference of the Echeneis to the Scorn- 

 brides is simply due to assumption piled on assumption. The 

 collocation need not, therefore, longer detain us. The posses- 

 sion by Echeneis of the anterior oval cephalic disk in place of a 

 spinous dorsal fin would alone necessitate the isolation of the 

 genus as a peculiar family. But that difference is associated 

 with almost innumerable other peculiarities of the skeleton 

 and other parts, and in a logical system it must be removed 

 far from the Scombridce, and probably be endowed with sub- 

 ordinal distinction. In all essential respects it departs greatly 

 from the type of structure manifested in the Scombridce and 

 rather approximates but very distantly the Gobioidea and 

 Blennioidea. In those types we have in some a tendency to 

 flattening of the head, of anterior development of the dorsal 

 fin, a simple basis cranii, etc. Nevertheless there is no close 

 affinity, nor even tendency to the extreme modification of the 

 spinous dorsal exhibited by Echeneis. In view of all these facts 

 Echeneis, with its subdivisions, may be regarded as constitu- 

 ting not only a family but a suborder. . . . Who can consistently 

 object to the proposition to segregate the Echeneidida as a sub- 

 order of teleocephalous fishes? Not those who consider that 



