ROOM III. 



DERMAL BOXES OF GONIOPHOLIS. 



173 



cheoDs, variously arranged, and which are the supports of the 

 dermal scales and spines. 



In the gigantic Gavial that inhabits the Ganges, and other 

 rivers of India, and which is remarkably distinguished by its 

 extremely slender, prolonged, beak-like muzzle, the nape of 

 the neck is protected by a complete shield, formed of sixteen 

 or eighteen transverse rows of dermal plates, of which there 

 are also six longitudinal series that extend down the back. 



These scutes are deeply corrugated externally, a struc- 

 ture adapted for the firm adhesion of the scaly integument ; 

 the largest in Dr. Grant's Gavial are 4| by 3 inches in 

 dimension. 



In the Swanage Crocodile the external surface of the dermal 

 plates (Lign. 40, fig. 1), is covered by numerous, irregularly 



LIGS. 4C. DERMAL BONE OF THE SWANAGE CROCODILE. 



1. The external surface. 



2. The inner surface. 



a. The lateral connecting process. 



not. size.) 



round and angular pits, or depressions, while the inner surface 

 (fig. 2) is smooth and glossy, and finely striated by decussating 

 lines, as in the dermal process of the Hylseosaurus. 



These scutes differ from those of all known recent and 

 fossil crocodilians in possessing a lateral conical projection 

 (a, Lign. 40), which fits into a depression on the under surface 

 of the opposite angle of the adjoining plate, resembling, in 



