44.8 Tlie Sifstema'ic Position 0/ Stylopliorus caiidiitus. 



inserted in tlie ligament between the coracoiJs and sometimes 

 directly articulated with them/' 



Stylopliorus agrees with the Ta^niosomi and differs from 

 tlie other Allotriognathi in the following characters : — 



" Body elongate. Skeleton feebly ossified; ribs feeble or 

 absent; lower pharyngeals reduced, toothless. No occipital 

 crest. Post-temporal simple ; pectoral pterygials plate-like, 

 two or three of them in contact with the coracoid. Fins 

 composed of simple flexible non-articulated rays; dorsal fin 

 very long ; anal short or absent *'"'. 



StyJo'phorus differs from the Tteniosomi in several respects, 

 of which the most important are the moderately compressed 

 body, which is eel-shaped rather than ribbon-sha[)ed ; the 

 very long lower jaw and backwardly directed suspensorium, 

 correlated with which is the reduction of the ptery go-palatine 

 arcade to a single small pterygoid element and the shifting 

 of the attachment of the branchiostegals from the lower to 

 the up])er edge of the cerato-hyal ; the cranium more de- 

 pressed posteriorly, with the epiotics se])arated by the supra- 

 occipital t, the frontals united by suture throughout their 

 length, the orbito-sphenoid absent and the vomer very small, 

 in position corres])onding to the posterior extremity of the 

 vomer in the Tseniosomi; the absence of neural and luemal 

 i^jiims and the fewer vertebra^, 53 in number. 



A special resemblance to Trachypterus is shown in the 

 structure of the caudal fin, which is divided into a lower 

 j)ortion with horizontal rays and an upper portion with the 

 rays directed upwards. 



I take this o{)portunity of calling attention to an excellent 

 account of the anatomy of Trachyplerus arcticns by Mi-. A. 

 Meek (' Studies Mus. Zool. Dundee,' i. 18^)0, pp. 55-77, 

 pis. i. & ii.) which I had previously overlooked and which 

 i)r. Starks also does not seem to have known. 



Dr. Starks is to be congratulated on having given us so 

 complete and careful an account of the anatomy of this 

 jjeculiar type, but his method of presenting his results is open 

 to criticism. His diagnosis of the suborder Atelaxia does not 

 give arjy clue as to its position in the system, and consists 

 almost exclusively of those features which distinguish it from 

 the Tajniosomi, whilst tiiose characters which the two groups 

 have in common are regarded as of minor importance and are 



* The anal fin is said to be absent in StyhpJwrvs, but Stark's figure 

 gliows an anal flu witli V2 rays in the niiddle of the length of tlie ji^sh • 

 this seems to be an instance of " artistic license." 



t Tlie nicetiug of the epiotics behind the siipraoccipital is often due tu 

 the elevatiuu uf the postfiior part of the cianiuni. 



