92 BULLETIN 18 8, UNITED STATES NATIONAL MUSEUM 



Mouth small, oblique; lower jaw with a moderately developed sym- 

 physeal knob ; rostral barbels well developed, maxillary barbels minute, 

 rudimentary, or lacking; pharyngeal teeth long, slender, uncinate, 

 biserial, with five teeth in main row and four in second row; gill 

 openings wide, extending under eye; gill membranes connected with 

 isthmus ; gill rakers short and comparatively few ; lateral line descend- 

 ing abruptly over basal part of pectoral fin and running thence near 

 the ventral profile to the lower half of the base of the caudal fin; 

 dorsal fin placed far backward, its origin in advance of anal and 

 nearer to caudal base than to tip of snout, branched dorsal rays 8; 

 caudal fin forked; anal rays usually 11 or 12, sometimes 8 to 10; 

 ventral fins short, inserted far in advance of dorsal. 



Genotype. — Daniops myersi^ new species. 



This genus may be found to intergrade with Danio of Hamilton 

 and to have only subgeneric rank. Although Danio in the strict sense 

 as set off from Brachy danio by Weber and cle Beaufort (1916, vol. 3) 

 was credited with 12 to 16 branched dorsal rays, species are known 

 [Z>. dangila (Hamilton), D. aeqmpinnatus (McClelland), D. tnala- 

 harica Masya and Indrambarya, D. neilgherriensis (Day), D. regina 

 Fowler, etc.] in which the branched dorsal rays are 9 to 11. The 

 Indian species D. naganensis Chaudhuri, originally described as 

 having 10 dorsal rays, has 9 branched rays according to Chaudhuri's 

 figure, and Hora and Mukerji (1934) in an artificial key to Danio 

 give the dorsal rays for the species as iii, 8, thus agreeing with Daniops 

 in this respect. 



An outstanding feature of this genus is the presence, in fully de- 

 veloped examples, of a backward-projecting shelf from the lachrymal 

 bone, corresponding with the spine seen in Danio regina Fowler and 

 other species. This shelf, as existing in most adults, may be of rec- 

 tangular shape or may have the two free angles rounded or produced 

 into points. 



Another diagnostic feature is the arrangement of the pharyngeal 

 teeth in two rows. Tliis number has been found to exist in all of 

 numerous specimens examined. All the references in the literature to 

 the pharyngeal teeth in Danio (Giinther, Weber and de Beaufort, 

 Day, etc. ) , indicate that such teeth are triserial, and this arrangement 

 has been confirmed in various species represented in the collection of 

 the U. S. National Museum. 



DANIOPS MYERSI, new species 

 FiGUKE 6 



Description. — Dorsal profile from snout to dorsal fin nearly straight, 

 ventral profile moderately convex; depth 3.5 in standard length; least 

 depth of caudal peduncle 1.2 in its length and somewhat less than 0.5 



