1894, PROCEEDINGS OF THE NATIONAL MUSEUM. 383 



Tills species lias not been seen by us, and we pbice it in tliis genus 

 witb some liesitatiou. Dr. Gilbert informs us tbat the pai'ietals are 

 united. 



III. Geuus A CUT OMENTUM, E i .,m- ii m u ii ii and IJ o(> so ii . 



Aiiilomenlum, Eigknmaw :\\ul Hkesox. Aiiht. Nat., July, 1S93 {ov(iHn). 

 Tyi'E. — Sebastodes ovalis, Avuks. 



This genus is composed of about four species. While these agree 

 with each other in the technical characters distinguishing the geuus, 

 they show considerable variation in other characters, .1. melanostomus 

 approaches Sehastichthi/.s in sliai>e of head and body. ^L oralis, on the 

 other hand, is a coin[»ressed fish with narrow head. In this last spe- 

 cies the shari) chin from which the genus derives its name is most 

 conspicuous. 



AXALYSI.^ OK THK SPECIES OE ACUTOMENTITM. 



a. Nuchal spines; skull wide, concavo between the large postocular spines. Lin- 

 ing of mouth and of gill-cavity black. .Short and deep; head heavy; mouth 

 large; lower Jaw projecting, maxillary reaching to below posterior border of 

 pupil. Eye ecjual to snout, 34 in head. Interorbital 4J iu head, jireorbital 3 

 in orl)it, with an anterior simple and a posterior many pointed spine. Maxil- 

 lary, niandilile, preorbital, and snout scaly. Scales of opercle rather large; 

 scales of the sides very large; accessory scales few. Gill rakers 34 in orbit. 

 Dorsal spines very low, about 4 in head; anal spines graduated. Scarlet, 

 shading into madder brown or blackish red above the lateral line. Fins ver- 

 milion, the lirst dorsal, with its membranes, narrowly Itlack edged. All other 

 fins more or less black on distal half, the caudal most so. Head vernulion, 

 tinged with black. Head 3] in the total length; D. XIII, 13; A. Ill, 7; 



lat. ]. J:l IMELANOSTOMUM, 1. 



aa. Nuchal spines or none ; gill cavity dusky. Elongate, (jeneral appearance otScbtis- 

 loiniis jirorhjcr. Head pointed, lower jaw projecting, maxillary reaching to 

 below jiosterior margin of eye, 2 in head. Interorbital slightly convex, with- 

 out ridges. Cranial ridges low, obscure, but all tciiniuatiiig in sharp si)iues; 

 pre- supra- and postocular, tympanic and o(ci])ital spir.cs present. Eye small ; 

 orbit li iu snout, 4| in head, 1,'; in interorbital. Prcorbital >J of an orbital 

 diameter, Avith 3 retrorse spines below, the posterior the smallest; a retrorse 

 spine just below the orbit. Opercular spines simple and strong. Mandible, 

 maxillaries, suborbitals, and entire snout scaled. Scales of the head small and 

 strongly ctenoid, those of the body larger. Outlines of spinous dorsal regu- 

 larly arched, the 4th and 5th spines highest, 3 in the head; highest articulate 

 ray 3f iu the head. Anal spines graduated, the second being stronger but 

 considerably shorti'r than the third, which is .5|- iu the head ; highest ray 3 in 

 the head. Pectorals extending somev/hat beyond the ventrals. Peritoneum 

 black. Top of head and back chiefly black, lateral line vermilion; a blackish 

 bana just below the lateral lino becoming much wider forward and extending 

 on the sides below the fifth dorsal spine. A large o])<-r(ular spot, a broad 

 band downward and backward from eye, a narrow one across cheeks below 

 the eye, lips and tip of lower jaw chiefly black; the rest of the head and sides 

 chiefly vei'miliou. Aual and ventrals Aermilion ; pectorals and caudal black- 

 ish; dorsals nearly black. Axils dusky. Head 3 in the total length; depth 

 3f; D. XIII, 13.i; A. Ill, 7i macdonaldi, 2, 



^aa. No uuchal spine; skull convexbetween thepostocularspines. Liniugof moutlj 

 (lud of gill-cavity pal(!. Cranial ridges low. Dorsals low. 



