J76 THE ANATOMY OF VERTEBRATED ANIMALS. 



The Hedgehog [Erinaceus JEuropceus) is pentadactyle and 

 plantigrade. It has a long flexible snout. The eyes are 

 small; the pinna3 of the ears are rounded, and the integument 

 lining the concha is produced into a transverse, shelf-like fold. 

 The under surface of the body bears hairs of the ordinary 

 kind ; but, on the dorsal aspect of the head and trunk, the 

 hairs are converted into strong fluted spines. There are 

 tvrenty-one dorso-lumbar vertebrae (of which fifteen are dor- 

 sal, and six lumbar), three or four sacral, and twelve to four- 

 teen caudal. Accessory processes, or metapophyses, are de- 

 veloped on several of the dorso-lurabar vertebrae. The sterne- 

 brsB are laterally compressed, except the manubrium, which is 

 broad ; and eight of the fifteen pair of ribs are connected with 

 the sternum. 



The occipital foramen is placed completely at the hinder 

 extremity of the skull, in the lower part of the perpendicular 

 occipital face of the cranium, and looks backward. There are 

 large paramastoid processes. The glenoidal surface for the 

 mandible is flattened. The zygoma is stout, and the jugal 

 bone is, as it were, applied upon the outer side of it. The 

 orbit has no posterior osseous boundary. The lachrymal fora- 

 men lies upon the face. There are unossified spaces in the 

 bony palate, and the posterior margins of the palate are thick- 

 ened, as in the Lemurs. The large and bullate tympanic bone 

 does not anohylose with the squamosal, or the periotic, and is 

 readily lost from the dry skull. The alisphenoid contributes 

 largely to the formation of the front wall of the tympanum ; 

 and a large portion of the inner wall of the tympanic cavity is 

 formed by a broad process of the basisphenoid, the outer and 

 lower edge of which joins, by a sort of harmonia, with the 

 inner and lower edge of the tympanic. 



The ascending portion of the ramus of the mandible is 

 short, and the angle is slightly inflected. The two rami are 

 not anchylosed at the symphysis. The supra-scapular fossa is 

 wider than the infra-scapular. The spine is strong, and the 

 acromion bifurcates, sending a prolongation backward. The 

 clavicles are long and convex forward. The humerus has an 

 intercondyloid foramen ; but there is no foramen above the 

 inner condyle, and this circumstance is unusual among the 

 Tnsectivora. The bones of the antibrachium are fixed in thg 

 prone position. There is an os centrale in the carpus, so that 

 it has nine bones. The scaphoid and lunare are anchylosed, 

 as in the Oarnivora, and the pisiform bone is much elongated. 

 The poUex and the fifth digit are the shortest. 



