PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. £(35 



Scales, cycloid, very small, and not or scarcely imbricated. 



Lateral line nearly straight and very faint. 



Head above oblong- and with a flattened straight upper surface fur- 

 nished with an adhesive oblong or elongated laminated disk. The eyes 

 are rather small, submedian, and overhung by the disk. 



Suborbital bones forming a slender infraorbital chain; the first or 

 preorbital triangular and thick. 



Opercular apparatus normally developed and unarmed. 



Nostrils double, close together. 



3Iouth terminal or, rather, superior, the lower jaw projecting, but 

 with the cleft nearly horizontal and not extending laterally to the eyes. 



Teeth present on the jaws and palate. 



Branchial apertures ample and fissured forwards. Branchiostegal 

 rays seven (or eight) on each side. 



The adhesive disk on the upper surface of the head is a modified first 

 dorsal fin and from the snout generally extends more or less posteriorly 

 on the nape and back 5 it is oblong or elongated and of an oval or ellip- 

 tical form, divided into equal halves by a longitudinal septum, and with 

 more or less numerous transverse pectinated or spiuigerous transverse 

 laminte in each division, the laminae being slightly erectile and depres- 

 sibie. 



Dorsal fin oblong or elongated, on the posterior half of the body 

 (including head), ending some distance from the caudal. 



Anal fin opposite and similar to the dorsal. 



Caudal fin rather small, variable in outline but never deeply forked. 



Pectoral fins moderate, inserted high on the sides. 



Ventral fins thoracic ; each with a spine and five branched rays. 



The vertebral column has vertebrae in slightly increased number, the 

 abdominal vertebrae being about twelve to fourteen and the caudal fif- 

 teen or sixteen. 



The stomach is ciecal and the pyloric caeca are present in moderate 

 numbers. The air bladder is obsolete. 



Who can consistently object to the proposition to segregate the 

 Echeneididae as a suborder of teleocephalous fishes ? 



iiTot those who consider that the development of three or four inar- 

 ticulated rays (or even less) in the front of the dorsal fin is sulficient to 

 ordinally diflerentiate a given form from another with only one or two 

 such. Certainly the difference between the constituents of a disk and 

 any rays or spines is much greater than the mere development or atro- 

 phy of articulations. 



Xot those who consider that tfie manner of depression of spines, 

 whether directly over the following, or to the right and left alternately, 

 are of ordinal importance; for such diftereuces again are manifestly of 

 less morphological siguificance than the factors of a suctorial disk. 



Xevertheiess there are doubtless many who will passively resist the 

 proposition because of a conservative spirit, and who will vaguely recur 



