6 H. B, POLLARD. 



The anterior narrower portion of the brain case, that is, from the 

 epiphysial bar forwards, is drawn out to a remarkable length, as indeed 

 are all the structures of the anterior part of the head. The hyoman- 

 dibular cartilage (H.M.) is triangular in form, the lower angle being- 

 produced into a strong process, which bears the operculum without the 

 intermediation of an opercular cartilage. An extensive but thin block 

 of cartilage (Qu) remains in the symplectic and quadrate region, and 

 sends inwards and forwards a short pterygoid process. 



The cartilaginous terminal portions of the prepalatine piece (Prepal.) 

 are shown in the figures, the part round about the articulation with 

 the preorbital process being replaced by bone. The prepalatine car- 

 tilage reaches almost to the tip of the snout. A small round block 

 (m.v.s.) between the ends of the prepalatine cartilages in the model 

 represents, in a very diagrammatic fashion, the premaxillary piece and 

 rudimentary median support of the velum. 



The Meckelian cartilage (Mck) has an inverted T-shape, the arms of 

 the T being long. The posterior arm does not reach the quadrate, the 

 quadrato-manclibular articulation being formed by bone. The upper 

 process is the coronoid process (Proc. cor.) which bears the long and 

 large procartilaginous coronoid piece (Cor. p.), which is continued into 

 a tentacle combining characters of maxillary and coronoid tentacle 

 (Mx. t.), in that it is continuous with the coronoid piece, and also 

 supported by the maxilla, which is attached to the end of the prepalatine 

 cartilage. The tentacle is directed outwards and backwards. The 

 anterior arm of the Meckelian cartilage is the mentomeckelian process 

 (M.mck.), which is very far from reaching its fellow of the opposite side. 

 I am inclined to think that it has not, at an earlier ontogenetic stage, 

 extended further. 



In the fleshy lower lip, there is a huge block of precartilage 1 

 (Merit, p.), with a projection directed posteriorly, while medially and 

 somewhat below this block may be seen on each side the mental tentacle 

 (Ment. t), which is actually supported by a lamina of precartilage, 

 lying superficially below the dentary bone. This supporting lamina 

 is of considerable extent. 



A submandibular tentacle (Subm. t.) lies below the coronoid process, 

 also with a superficial supporting lamina of precartilage. 



1 Better termed Extramental. 



