326 APPENDIX. 



The first socket (b) is three lines in transverse breadth : 

 the second socket, (c) which answers to the first in Halt- 

 core indicus, (fig. 2, c, as shewn in *the figure of a portion 

 of a skull of an individual of that species corresponding 

 in age with the Balicore australis, fig. 1), is four lines and 

 a half in breadth, indicating a proportionately larger tooth : 

 the third socket (d, fig. 1), answering to the second in fig. 

 2, is nearly six lines across its outlet, and a narrow longi- 

 tudinal ridge along its outer wall, indicates the implanted 

 part of the molar to have been impressed with a longitudinal 

 channel, like the anti-penultimate molar in Halicore indicus. 



The ante-penultimate socket in Halicore australis (fig. 

 1, e) has not the ridge projecting from its outer wall : its 

 aperture is seven lines and a half across ; whilst its cor- 

 responding socket in Halicore indicus (fig. 2, e) is only 

 six lines across, and it shews the ridge along its outer wall, 

 which impresses the implanted part of the tooth. 



The penultimate socket (fig. 1, f) is also larger in 

 Halicore australis than in Halicore indicus, (fig. 2, f) ; 

 indicating the specific superiority of size in that tooth. 

 The rudiment of the last molar in Halicore australis, 

 agrees in size as well as shape with that in Halicore indicus. 



The above comparisons refer to the molars of the upper 

 jaws; but the same differential results are yielded by the 

 lower jaws of the two species. 



Comparative admeasurements of the two skulls of ma- 

 ture individuals of the species Halicore australis and 

 Halicore indicus, of the same sex, and at the same age, 

 viz. before the ante penultimate molar has been shed and 

 when the sockets of the anterior molars have been obli- 

 terated, shew the Halicore australis to have a smaller head, 

 and most probably to be a smaller animal, than the 

 Halicore indicus. The specific distinction is, however, 

 more decidedly manifested by the difference in the dental 



