Fishes of the JVestern North Atlantic 



491 



ends of nostrils; distance between inner ends of fifth gills about 300/0 as great as 

 distance between first gills. 



Nasal openings strongly oblique, all but their outer ends roofed over by nasal 

 curtain; distance between outer ends of nostrils 60-65 °/o ^s great as breadth of head 

 at level of mouth; outer posterior margin of nostril with a broad subtriangular lobe 

 extending inward over nasal aperture, visible if nasal curtain is rolled back; nasal curtain 

 short, its outer corner about a right angle, slightly blunted, its free posterior margin 

 nearly straight, smooth-edged, and free from upper lip throughout its length; its in- 

 ternal surface, near outer end, with a transverse fold, the free edge directed toward 

 center of mouth. Mouth occupying about ^/^ of breadth of head; lower jaw bowed 



Figure 114. Mobula kypostoma. Ventral view of 

 pelvic fins of female pictured in Fig. 113, about 

 0.6 X. 



slightly forward; distance from upper jaw to front of head about 1/3 as great as breadth 

 of mouth and about 90 "/o as great as distance between inner ends of fifth gill openings. 

 Tooth bands narrow, fusiform, flexible, only loosely attached to the jaws; occupying 

 median 45-47 "/o of upper jaw and slightly less of lower jaw in specimens seen; per- 

 haps relatively longer in largest individuals. 



Teeth 33 in female 836 mm wide, |g in female 1,070 mm wide"; teeth of females 

 ovate, diamond-shaped, squarish or rectangular, of different sizes (all variations some- 

 times present on same individual), without cusp ; anterior margins straight or somewhat 

 arched or roughly triangular, but with indistinct scalloping; posterior margins with 

 1—3 low subtriangular rounded prominences; teeth of males more closely crowded, 

 usually with two but often with one or three (occasionally four or five in lower jaw) long, 



91. 1^ on male and ^ on female, reported by Radcliffe (Bull. U. S. Bur. Fish., 34, 1916: 279). The original account 

 of the species credited it with 80 series of teeth. But Dumeril (Hist. Nat. Poiss., 1865: 657) has pointed out that this 

 larger number no doubt resulted from inclusion of more than one row of teeth in the count. 



