18 



In the upper jaw the incisors are four in number, and apart ; the two 

 middle are large, sub -cylindrical, elongated, and placed at the apex 

 of the jaw ; the two others are small, and seated behind the former. 

 Separated from these by a small space, succeed the canines, similar 

 in character to the incisors, but stouter and with a slight posterior 

 notch. The molars are five on each side : the first false and simple ; 

 the three next transversely elongated, with two external tubercles in 

 contact, and one internal ; hence their crowns assume the form of an 

 elongated triangle, the apex being internal ; the fifth molar is a 

 slender lamina transversely placed, but not advancing so far laterally 

 as the molar preceding it. 



The under jaw presents two small incisors, somewhat apart from 

 each other, and directed obliquely forwards ; behind these there 

 follow on each side in succession three larger and conical teeth, di- 

 rected obliquely forwards, and which may be regarded as false molars. 

 Separated from the last of these by a small space, succeed four molars 

 on each side, vertical and smaller than those above, with two tuber- 

 cles internally and one externally, so that the worn surface is trian- 

 gular, with the apex outwards ; the last is the smallest : the surfaces 

 of all are apart, but their bases are in contact. 



Mr. Martin observes, that this system of dentition (very distinct 

 from that which characterizes the Tenrecs, (Centenes,) and the ge- 

 nus Ericulus of Isidore GeoiFroy) presents us with characters which 

 decidedly separate Echinops from Erinaceus, notwithstanding their 

 approximation. In Erinaceus the upper incisors are six ; there are 

 no canines, but three false molars on each side, and four true molars, 

 of which the last is small and narrow ; the others square, with two 

 outer and two inner tubercles ; while in the lower jaw, the incisors, 

 two in number, are very large, followed on each side by two false 

 molars, and four true molars. In Echinops, as in Erinaceus, the feet 

 have five toes ; the thumb of the fore-feet is small and seated on the 

 ■wrist, the other toes are small, and armed with feeble, compressed, 

 hooked claws, the last toe the smallest : the toes of the hind-feet 

 resemble those of the fore-feet, and the inner and outer are the 

 smallest. The snout, ears, tail, and spiny covering of the upper sur- 

 face of the body, as in Erinaceus. 



In addition to the above description of the external characters of 

 Echinops, Mr. Martin communicated to the Meeting some details of 

 the anatomy of the soft parts, but the condition of the specimen was 

 not such as to enable him to give any very complete account of the 

 appearances presented by the internal organs. 



The skull, as compared with that of Erinaceus, was proportion- 

 ally very inferior in size ; it was more level above, and narrower, 

 the cranial cavity being contracted, and the muzzle shorter. The 

 occipito-parietal ridge was elevated, the zygomatic arches were 

 almost obsolete. The palate was narrow, and the posterior /orffwzwa, 

 which in the hedgehog are large open fissures, were reduced to mi- 

 nute orifices. 



The pelvis was very narrow, and the pubic bones were separate 

 in front. 



