554 Bulletin 4y, United States National Museurn. 



257. MACROSTOMA,* Risso. 



Jl/ucj-ostoma, Kisso, Europe Mt-rid., m, 447, 1826, ((iHi/M,s((</eii.s) ; not 3facj-osto)n(S, WiED, 1817, a 



genus of insects. 

 Noloscopehif, Gunther, Cat., v, 405, 411, 1884, (resplendens). 

 Catablemella, Eioenmann & Eigenmann, Proc. Cal. Ac. Sci., 2d series, iii, 1890, 24, (brachyrhir). 



Myctophids with the dorsal fin much longer than the anal, and overlap- 

 ping the anterior half of the latter. Body elongate. Snout obtusely con- 

 ical ; .iaws equal in front; cleft of mouth nearly horizontal; maxillary 

 not dilated behind. No luminous glands on head or tail. Arrangement 

 of photophores irregular. Precaudals 2 -f 1 or 2, the last one high up. 

 {unKjj'oc, large; aro/ia, mouth.) 



a. Mediolaterals 3, in a curved, subvertical series; posterolaterals 2 or 3. 

 b. Posterolaterals 2, horizontallj' side by side, under adipose dorsal. 



<•. Caudal spots 3(2 + 1); posterolaterals under soft dorsal; pectoral weak and short. 



d. Dorsal rays 21 ; anal 20; scales 42; anal photophores 8 + 8. quercinum, 828. 



dd. Dorsal rays 16; anal 14; anal photophores 9 + 17. maroaritiferum, 829. 



cc. Caudal spots 4 (2 + 2); first posteiolatcral under adipose dorsal, second behind it. 



D. 21 to 24; A. 17 or 18; anal series 8 or 7 + 6 or 7. angustidens, 830. 



bb. Posterolaterals 3, horizontally side by side; caudal spots 3 (2 + 1); last posterolateral 



under adipose dorsal; pectoral short and weak. D. 20 or 21; A. IC; scales 46; anal 



series 9 + 4. castaneum, 831. 



aa. Mediolaterals 2; posterolateral 1; caudal spots 3, the last at end of lateral line. D. 20; A. 



18; scales 36. caudispinosum, 832. 



828. MACROSTOMA QUERCINUM (Goode & Bean). 



Head 3f to 4 ; depth 5|. D. 21 or 24 ; A. 19 or 20 ; scales 42. Eye 

 moderate, nearly 4. Snout short, about i as long as the diameter of the 

 eye. Mouth oblique and very large, the maxillary extending to angle 

 of preoperculum. Length of upper jaw about ^ that of head. Origin 

 of dorsal much nearer tip of snout than root of caudal, being over the 

 twelfth scale of the lateral Hue and immediately above origin of ventral ; 

 length of its base equal to that of head, and longest ray f as long as head, 

 its end over seventh ray of anal; pectoral short, not reaching to origin 

 of ventral ; anal origin about under twenty-first scale of lateral line, 

 the length of the base equals that of head without snout, and the longest 

 ray is about i as long as head; adipose fin very slender, its distance 

 from end of dorsal equaling + length of head; caudal moderate, deeply 

 forked. A large luminous spot near the angle of the preoperculum ; 2 

 above the pectoral base and 1 below it; 1 just below the lateral line 

 above the origin of the anal ; 5 or 6 between the isthmus and the root of 

 the ventral; a number of others not accurately counted. Color dark 

 brown. 



Mediolaterals 3, in curved subvertical line; posterolaterals 2, under the 

 soft dorsal; precaudals 2 -(- 1, the last below the end of the lateral line > 

 one of the precaudals very high up. Western Atlantic, at 700 to 800 

 fathoms; also in the Mediterranean. (Goode & Bean.) This is very likely 



*By the rules of the Amer. Ornithol. Union, Xolosropehis should be used instead of Bfacrosloma, 

 as there is a prior genus Ulacrostomus. We regard the two as distinct, as they are spelled differ- 

 ently. 



