1941 CATALOGUE OF FISHES OF TORTUGAS 279 



fore, it is misleading to say "head partly naked" as Goode and Bean have done 

 in their key. 



The following proportions and enumerations are based on 3 specimens in the 

 collection, 64, no, and 140 mm. long to base of caudal: Head 4.9, 5.25, 5.0; depth 

 7.1, 5.8, 5.6; from snout to origin of dorsal 4.6, 4.3, 4.25; from snout to vent 2.9, 

 2.6, 2.8. Eye in head 4.7, 3.8, 4.75; snout 4.0, 4.4, 4.75; maxillary 1.7, 1.75, 1.75; 

 pectoral damaged, about 2.0. D. about 100; A. about 85; scales between upper 

 angle of gill opening and vertical from origin of anal about 40; gill rakers 24; 

 branchiostegals 8. 



The color of the preserved specimens is uniform brownish. 



The compressed head and body; lateral eyes; fully scaled head; large mouth, 

 with maxillary extending beyond posterior margin of eye; bands of villiform 

 teeth on the jaws, vomer, and palatines; and small ventral, inserted on the 

 isthmus, and composed of a single simple filament are useful in characterizing 

 the genus and species. 



West Indies and Gulf of Mexico, in deep water. S. F. H. 



Diplacanthopoma brachysoma Giinther 



Dr. Longley listed this species in his field data at least four times, from depths 

 of 205 to 392 fathoms. As many as 10 specimens are listed from four hauls, 7 

 having been taken in a single haul at 290 fathoms. The fish ranged in length 

 from 106 to 200 mm. 



The collection contains 7 specimens, 90 to 200 mm. long. 



Body compressed, tapering gradually into a slender pointed tail, notably longer 

 than head and trunk; head almost flat above, about as wide as deep at posterior 

 rim of orbit; bones about eyes and snout quite cavernous; eye placed high, 

 slightly supralateral, a little longer than the short, broad snout; mouth broad and 

 oblique, with a broad maxillary reaching opposite posterior margin of eye; teeth 

 all small, villiform, in bands on jaws, vomer, and palatines; gill rakers short and 

 spinulate; opercle with 2 strong spines, one vertical, the other horizontal, form- 

 ing a right angle between them; snout bearing a very short, compressed median 

 spine situated about opposite anterior margins of orbits; scales small, cycloid, 

 longer than deep along side, and missing on head; dorsal and anal fins of about 

 equal height and fully confluent with caudal, the origin of dorsal scarcely an 

 eye's diameter behind vertical from base of pectoral; pectoral moderately long, 

 but failing to reach vent; each ventral consisting of a mere filament, enclosing 

 2 rays inserted close together and about an eye's diameter in advance of pectorals. 



The following proportions and enumerations are based on 3 specimens, 158, 

 178, and 200 mm. long: Head in total length, 5.0, 4.7, 4.8; depth 8.o, 7.1, 10.0; 

 distance from snout to vent 2.5, 2.25, 2.4; snout to origin of dorsal 4.0, 3.9, 3.8. 

 Eye in head 4.25, 4.5, 4.8; snout 5.5, 4.75, 5.7; maxillary 2.0, 2.0, 2.1; pectoral 2.0, 

 1.8, 1.5. Scales between upper anterior angle of gill opening and vertical from 

 origin of anal about 48; P. 21, 22, 23; gill rakers 12, 13, 13. 



Sexual dimorphism is very strong, the genitalia apparently being similar to 

 those of Dinematichthys cayorum (see p. 278). 



Dr. Longley has the following on color: "Faintly brown above, almost white 



