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Memoir Sears Foundation for Marine Research 





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Figure 117. Manta birostris, juvenile male, 11 feet 5 inches wide. A Part of lower dental band from outer 

 fifth of jaw, with anterior edge uppermost, about 5.7 X • 5 Teeth from same, to larger scale, about 1 7 X . C Lateral 

 view (below) and posterior view (above) of tooth, about ij X. D Dermal denticles, dorsal surface, with anterior 

 ends uppermost, about 1 2 X . £ Lateral views of larger and smaller denticles (below) with anterior ends to the 

 left, and axial view (above), about 12X- F Dermal denticles from ventral surface with anterior ends uppermost, 

 about 12 X. G Lateral view of larger and smaller denticles from ventral surface (above), and axial view (below), 

 about 12 X. 



small, their extreme breadth only about 5-6 "/o as great as breadth of mouth; outer 

 contour of nasal curtain nearly rectangular with rounded corner; its rear margin smooth; 

 weakly concave along median sector with the edge only narrowly free from upper lip; 

 internal face of curtain, near outer end, with a thin transverse fold directed toward 

 center of mouth (Fig. 116E). 



Mouth occupying more than half (about 63 "/o) of extreme breadth of head, its 

 corners without distinct furrows; lower jaw weakly convex forward, somewhat over- 

 lapping upper jaw, its anterior edge thick, rounded; upper jaw without teeth, but upper 



