Dr. J. E. Gray on a Four-bearded Water- Terra^fin. 303 



varieties and subvarieties figured and described by Keuss and 

 others. 



On close examination of specimens and collation of lists, we 

 find tliatj as with GJohigerituey so with Bofalina', it is by the 

 increase of varieties the distinction is chiefly made between 

 the Foraminiferal faunae of the past and of the present seas. 



[To be continued.] 



XXX. — On a Four-hearded Water-Terrapin from North 

 Australia. By Dr. J. E. Gray, F.R.S. &c. 



The British Musemii has received a very young freshwater 

 Terrapin belonging to the family Hydraspidaj, from Cape 

 York, North Australia. It agrees with the genus Elseya in 

 having no nuchal shield, and in having the back of the neck 

 furnished with regular longitudinal rows of small conical 

 spines. The skin over the temporal muscles is divided into 

 irregular convex tubercles ; the crown of the head is covered 

 with a continuous soft skin, which becomes hard when 

 dried. 



This specimen differs from all the known species of Elseya 

 in having four beards — that is to say, two short cylindrical 

 beards on each side of the hinder edge of the lower beak. 

 The two front are in the place where beards are usually found 

 in the genus, the two hinder at some distance behind them. 



The head and back of the neck are dark olive ; the beaks 

 are greyish white, with a broad white streak from the angle 

 of the mouth extending behind towards the shoulders. This 

 streak is separated from the white throat by a black streak on 

 its lower side, which is extended in front, and forms a narrow 

 margin to the back edge of the lower beak. The back of the 

 shell is dark olive, the areolae occupying nearly the whole of 

 the plates ; the front marginal shields with numerous minute 

 spines ; nuchal shield none. The underside of the marginal 

 shields and the sternum white, with a very narrow edge to the 

 marginal plates ; a dark oval spot on each side of the suture 

 between the second and third and hinder plates. 



This may be the type of a new genus characterized by the 

 four beards ; but I think it is most likely an accidental variety 

 of Elseya latisternum. We must wait until we obtain more 

 specimens to determine this point, more especially as the top 

 of the head wants the hard surface of the older specimen of 

 that genus. 



