2 28 Btdletin American Museum of Natural History. [Vol. XIX, 



respects resemble those of the Leptictidae. The reduced pre- 

 molars and short facial portion of the skull exclude it from 

 the Gymnurinae, but the teeth resemble quite nearly those of 

 Necrogymuitrns,^ and the palate does not show the defective 

 ossification of Erinaccns. The last molar is small and tritu- 

 bercular as in Hylomys, Necrogymnnrus, and Galcrix. In 

 Gymnura it is large and extended longitudinally; in Eri)iaceits 

 small and reduced to a transverse blade. The teeth are more 

 extended transversely than those of Erinaceus, and retain 

 considerable indications of the tritubercular form of molar 

 from which they no doubt originated. Their pattern, how- 

 ever, is definitely Erinaceid, with two equal outer and two 

 equal inner cusps, a smaller separate median cusp (meta- 



conule), and an an- 

 tero-median ridge 

 from the antero-inter- 

 nal cusp (protocone) 

 to the antero-external 

 cingulum. 



This hedgehog 

 forms a connecting 

 link between the Eri- 

 naceine and Gymnu- 

 rine subfamilies, and 

 to some extent be- 

 tween Erinaceidse and 

 Leptictidae. It seems 

 impossible to place it 

 in any of the described 

 genera, and it is there- 

 fore named: 



Proterix loomisi, gen. 

 et sp. nov. 



Dentition ^jIjAiA' V 

 enlarged. C^ large, two- 

 rooted. P^ small, one-rooted. P^ small, three-rooted with well de- 

 veloped deuterocone. P4 large, molariform, with small hypocone. 



' Relying on Dr. Leche's very careftil figures and descriptions. 



Fig. I. Proterix loomisi. Type specimen, twice 

 natural size. A., anterior part of skull from above; W, 

 palate from below. 



