1906.] NATURAL SCIENCES OF PHILADELPHIA. 511 



Head rather large, compressed, upper profile nearly straight from 

 tip of snout to origin of spinous dorsal, and lower a little more incHned 

 and convex. Snout rather short, its length about f its width, and 



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Fig. 1. — Dules marginatus boninensis Fowler. (Tj'pe.) 



rather truncate in front. Eye rather large, rounded, high and anterior, 

 or posterior margin of pupil about midway in length of head. Mouth 

 inclined, moderate, opening superiorly, and with mandible protruding 

 in front. Maxillary narrow, free for about half its length, and its 

 distal expansion about f diameter of pupil. Teeth in jaws rather 

 small, in bands. Vomer and palatines with patches of minute teeth. 

 Tongue rather narrow, edentulous, pointed, and free in front. Buccal 

 membranes rather narrow. Nostrils close together, superolateral, 

 and much nearer front of eye than tip of snout. Interorbital space a 

 little broad, slightly convex, and with frontal ridges little prominent. 

 Margin of preorbital dentate. Lower margin of preopercle finely 

 dentate, and posterior margin entire. Opercle with 2 fiat backwardly 

 directed pointed spines, well separated, and lower larger. Supra- 

 scapula with several rather coarse serratures. 



Gill-opening extending forward about opposite front margin of 

 orbit. Gill-rakers 10 + 21, lanceolate, slender, finely asperous inside, 

 and longest about ^ of orbit. Gill-filaments a trifle less than diameter 

 of pupil. Isthmus narrowly compressed, and with a median groove. 



Scales finely ctenoid, above lateral line in series parallel with its 

 course, below in horizontal series, along bases of vertical fins small and 



