122 



THE ANATOMY OF VERTEBEATED ANIMALS. 



sented (Fig. 30, /, g, h). In some genera a basket-like carti- 

 laginous apparatus strengthens the walls of the oral cavity ; 

 while, in others, such a framework supports the giU-sacs. 

 The Marsipobranchii possess neither the pectoral nor the 



Fig. 30.— A, the skull of a Lamprey, viewed frcjin the side; B, from 

 above -.—a, the ethmovomerine plate ; b, the olfactory capsule ; c, the 

 auditory capsule ; d, the neural arches of the spinal column ; e, the 

 palato-pterygoid portion,/, probably, the metapterygoid, or superior 

 quadrate, portion, and ff, the inferior quadrate portion, of the 

 subocular arch; h, stylohyal process; ;', lingual cartilage; k, in- 

 ferior, /, lateral, prolongation of the cranial cartilage ; 1, 2, 3, 

 accessory labial cartilages ; m, branchial skeleton. The spaces on 

 either side of 1 are closed by membrane. 



pelvic pair of limbs, nor their arches. Horny teeth may be 

 developed upon the roof of the palate, or upon the tongue, 

 or may be supported by peculiarly developed labial carti- 



