HAMMERHEAD SHARKS — GILBERT 



59 



perpendicular to the body axis* anterior margin of lower caudal lobe 

 weakly convex toward base, more strongly convex toward apex; 

 posterior margin of lower caudal lobe nearly straight. 



Anterior margin of rostral node of chondrocranium varying sUghtly, 

 from broadly convex to broadly and shallowly concave; rostral 

 fenestra absent; anterior fontanelle (viewed dorsally) deep and broadly 

 U-shaped, with the sides of the U slanting slightly inward; a distinct 

 median notch present on anterior fontanelle; fairly prominent (though 

 not as prominent as in S. tudes) , broad, obtusely pointed wings present 



200 250 300 350 400 450 500 650 600 660 700 760 800 860 900 960 

 TL IN MM 



Figure 16. — Comparison of snout length in Sphyrna media and Sphyrna corona. (Figure 

 by Paul Laessle.) 



on sides of rostral node; anterior wing of olfactory cartilage fairly 

 prominent (though not as prominent as in S. iudes), pointed, and pro- 

 jecting medially; tip of anterior part of preorbital process short (not 

 as short as in S. mokarran) and rather thick, with a sharp angle on 

 the anterior edge. 



Total number of vertebrae 191 to 196 (10 specimens examined); 

 body vertebrae 100 to 103, there being from 7 to 14 more body than 

 caudal vertebrae. 



14-1-13 14-1-14 14-0-14 13-2-12 13-2-13 , 13-1-12 



Teeth 



14-1-14 14-1-14 13-1-14 14-1-14 14-1-14 



13-1-13 



