3()2 



MR. C. FORSTER-COOPER ON 



SOHIZOTHERIUM PILGRIMI, Sp. n. 



Pilgrim also mentions the j^i'esence of a smaller form in these 

 deposits, indicated by some fragments too much worn for accurate 

 description. In the present collection are two unworn and per- 

 fectly preserved upper molars (Plate I., central figure) of an 

 iinimal much smaller than those of the species just described, 

 and whicli may belong to Pilgrim's undescribed species although 

 even a. shade smaller than the latter. 



The smaller size of these teeth suggests at first that they are 

 milk teeth, but there are certain arguments against this view, 

 wliich is not adopted here. The specimen fortunately has just 

 enough of the anterior part on the zygomatic arch to show the 

 relative position of the teeth in the maxilla (text-fig. 3). A 

 reference to Holland and Peterson's figure * shoAvs that in the 



Text-fio-vire 3. 



Scliisotherium ? pilgrimi. 1st and 2nd xipper molars in side view, showing their 

 position relative to the zygomatic arch. The position of the antorbital foramen 

 is marked with an *. Nat. size. Type-specimen. 



milk and permanent molars of Moropus the last milk tooth lies 

 well in front of the anterior root of the maxillary process of the 

 zygoma, the first molar under the root of this process, and 

 the second under its posterior border. If the present specimen 

 is grown in a similar way, it supports the view that the teeth are 

 the first two true molars. The anterior tooth is slightly worn, the 

 second only just erupted. Beneath them there are cavities without 

 trace of successional teeth and too small to allow of them. The 

 teeth being fully formed and pi-actically in wear, the germs of the 

 succeeding teeth would have been comparatively well developed. 



Moreover, of two fragments of lower jaws one has the last milk 

 molar fairly well worn and the front part of the first lower molar 

 just erupted. One side of this specimen has been ground aAvay, 

 and the section (text-fig. 4) shows the last milk molar with the 



* Loc, cit. pi. li. figs. 1-2. 



