68 DR. A. SMITH WOODWARD ON REMAINS OF [Jan. 23, 



of the other specimens is less deep at its hinder fork and has a 

 more slender descending process. 



The hinder portion of the second skull already mentioned (no. 2) 

 comprises the occiput and brain-case as far forward as the front 

 of the cerebral hemispheres. It is much battered and broken, and 

 in quite as fresh a state as the cranium already described, with a 

 considerable investment of dried soft parts on its base. It is only 

 very slightly smaller than no. 1, but is of interest as exhibiting 

 some of the sutures, besides a roundness and smoothness indicative 

 of immaturity. The supraoccipital is shown to be very large ; a 

 small median point of it enters the foramen magnum, while the 

 suture separating it from the parietals and squamosals extends 

 along the rounded lambdoidal ridge. The horizontally-extended 

 suture between the squamosal and parietal on the inner wall of 

 the temporal fossa is seen in the position where Owen determined 

 it to occur in Mylodon \ Both tympanies are preserved, but they 

 are more obscured by soft parts than in no. 1. 



To this cranium probably belongs a detached portion of the left 

 side of the facial region (no. 5), in a similar state of preservation 

 and slightly smaller than the maxilla no. 4 (PI. V. tig. 2). The 

 suture between the frontal and the maxilla still persists, while the 

 oral border is preserved further forward than in the last-mentioned 

 specimen, showing a fragment of the much-reduced premaxilla 

 united with the maxilla by a jagged suture. 



The third imperfect occiput, comprised among the fragments 

 numbered 3, is about as large as the immature specimen no. 2, but 

 does not exhibit any features worthy of special note. 



The largest and most important portions of the mandible are 

 nos. 9 and 11, which evidently belong to the right and left rami of 

 one and the same jaw. They are much broken and are in the same 

 fresh condition as the skulls, with traces of the periosteum and 

 even considerable portions of the soft parts of the gum. The 

 right ramus (PI. VI. fig. 2) is preserved sufficiently far forwards 

 to show that there was no caniniform tooth in front of the series 

 of four ordinary molars. Judging by the extent of the latter 

 series, the specimen probably belongs to the same individual as the 

 skull no. 1. 



Another portion of a mandibular ramus (no. 10) of the left side 

 is slightly smaller than the last and may well have belonged to 

 the immature individual no. 2. It is similarly quite fresh in 

 appearance, and bears the shrivelled remains of the gum. It is 

 interesting as exhibiting the two posterior molars slightly different 

 in shape from those of the former mandible. In this specimen 

 (PI. VI. fig. 3) the longer axis of the third molar is oblique, 

 whereas in no. 9 (Plate VI. fig. 2 a) it is coincident with the axis of 

 the mandible ; while in the former the fourth molar is not so long 

 in proportion to its width as in the latter. Such slight differences, 



1 R. Owen, ' Description of the Skeleton of an Extinct Gigantic Sloth. 

 Mylodon robustus, Owen ' (1842), p. 18. 



