128 Cc. H. DANFORTH 
The transverse muscles reach their maximum development in 
Amia and teleosts. They are generally considered in the same 
category as the oblique muscles (interarcuales), and Vetter classes 
the single ventral transverse muscle in Acipenser as the inter- 
Fig. 6 The dorsal transverse muscle of the pharynx 
Fig. 7 Pharyngoclaviculares and ventral muscle of the pharynx 
arcualis ventralis V. If it be such, both its origin and insertion 
have migrated back to a marked degree. Good evidence on this 
point is apparently not to be sought in the adult Polyodon. 
Possibly the embryology may throw some light on the question. 
