"""iMo"'] PROCEEDINGS OF THE NATIONAL MUSEUM. 247 



Bt'anchial apertures small, vertical, mostly in front of the anterior 

 bases of the pectorals, and consequently separated from each other by 

 a very wide isthmus. 



BranchiOfttegal rays six, three perceptible in the smooth, movable 

 portion of its membrane, the fourth quite straight, enveloped in the 

 part of the skin by which the membrane unites with the throat, and 

 the two others concealed by the skin of the throat and by the scales 

 with which it is furnished. (C. V.) 



Dorsal Jins two, the anterior with six or eight heteracanth spines, the 

 foremost two of which are generally more or less detached ; the pos- 

 terior fins with only eight to ten rays, most of which are simply articu- 

 lated and rather short ; between the two fins is a compressed lancet- 

 like spine, immovably connected with the interspinal below. 



Anal fin opposite and nearly coterminal with the second dorsal, 

 short, and with only six articulated rays. 



Caudal fin emarginate, with its lobes nearly equal and with few rays, 

 e. g., seven or eight complete and two unbranched or rudimentary 

 above and two or three below.* 



Pectoral fins greatly specialized, expanding in a horizontal plane and 

 composed of two distinct portions; an anterior or upper small, and 

 an inferior or posterior enlarged portion, the former composed of five 

 or six rays, the latter of numerous long and slender unbranched rays, 

 and a number of short graduated ones forming a kind of axillar fringe ; 

 all connected by membrane which is but slightly emarginated about 

 the middle between each pair of rays. The fins are underlaid by the 

 very elongated spines of the preoperculum. 



Ventrals thoracic, separated by a narrow interval, and composed of a 

 spine and four unbranched rays, the innermost of which are short and 

 slender. 



BrancMw complete and with the last arch separated by a cleft from 

 the hypopharyngeals and oesophagus. 



Branchial raJcers rudimentary or absent; pharyngohrancliial bones 

 three on each side ; the third enlarged and deutigerous {epipharyngeal), 

 the other rudimentary and edentulous. 



Fseudohranchiw developed. 



It will appear from this description, when compared with those of the 

 Triglidfe and the Peristediidai, thus the Dactylopterida^ differ in almost 

 all respects from those forms with which they have been associated, 

 and in fact the only reason for ever having brought them together is 

 the fact that both have a head furnished with a casque, or armed, but, 

 as already indicated, this casque is extremely different in the two types. 

 Possibly another character is that there is a good deal of red about the 

 body, for, absurd as such a cause would be, it has evidently influenced 



* The formula may be 1 (small, simple) -f I (large, simple) + 4 (brauched) -f 3 

 (branched) -f- 1 (large, simple) +2 (small, simple). 



