No. 468.) MUSCLES OF ACANTHIAS AND RAIA. 893 
spiracle in front of the spiracular cartilages, and are inserted 
upon the inner surface of the lower jaw just below the *coro- 





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MM 
Ati 
DE DL et 
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Fic. 1.— Ventral muscles of Acanthias after removal of skin. Az, adductor mandibularis ; 
Cac, coraco-arcualis communis; Csz 7-6, constrictores superiores ventrales; Csv ra, con- 
strictor superioris ventralis, anterior fibers; Gs, gill slits; Z/s, levator labialis superi- 
oris; 2, tendon in adductor mandibularis : 

noid' process. The general course of the fibers is curved, 
while that of the levator maxillae superioris is straight, the only 
