26 



Moles make a variety of subterranean passages according to the age and tet 

 of the borer. Small and frequent mounds thrown up from a tunnel made 

 near the surface of the ground are said to be the work of the female mole 

 when she is not able to make deeper burrows. These passages take no positive 

 direction. The two chief architectural works of the mole are the fortress and the 

 nest. 



The fortress consists of a small hillock made of compact earth. Near the sum- 

 mit of this mound or hillock is a circular gallery, and another gallery near 

 the bottom. These two galleries are connected by five short passages. In the 

 centre of the hillock is a spherical chamber connected with the lower gallery by 

 three passages, and out of the spherical chamber there is a large passage leading 

 under the lower gallery and into one of the great high roads which connect the 

 fortresses ; also a number of smaller burrows radiate from the lower gallery. 

 This is the home of the mole in the winter and during hours of repose, and by 

 the complicated arrangement of passages it is able on the approach of danger 

 quietly to slip away. 



The nest is a simpler strueture than the fortress, and placed generally some 

 distance from it, and often in a bank of a ditch. It consists of a large circular 

 chamber, which is at the breeding time in April and May filled with leaves 

 and moss. 



It does not appear, therefore, that any of the passages of the mole are always 

 made in a circular form, except those in the fortress, but no doubt occasionally 

 it may be convenient for the mole to adopt this form of tunnel. 



Passing on now to the next genus of British insectivora we come to the 

 shrews belonging to the genus Sorex. 



There are said to be 4 different species of British Shrew, but it is pos- 

 sible these are only varieties ; however this may be they are distinguished by 

 the titles of the common Erd Shrew (Sorex-vulgaris), the Water shrew (Sorex- 

 fodiens), the Oared Shrew (Sorex-ciliatus), and the Rustic Shrew (Sorex-rustica.) 



The first two of these are very common in England, the third less so, and 

 the fourth is found frequently in Ireland but rarely in England. 



The whole appearance of the shrews is so much like that of a mouse that 

 most unscientific persons would at once class them together; it is only necessary, 

 however, to compare a shrew's and a mouse's mouth to see at once that they are 

 very differently formed animals ; the mouse has only two large incisor teeth in 

 each jaw, then a wide gap, then three molar teeth with flat crowns ; whereas 

 the shrew has six sharp incisors in the upper and four in the lower jaw, which 

 latter stick out nearly horizontally, and a number of tuberculate molars. The 

 teeth alone therefore are quite sufficient to separate the shrews from the mice ; 

 these latter animals belong to the order of Rodents and are allied to tho rab- 

 bits, rats, &c., and their diet is entirely vegetable ; the shrews on the other hand 

 feed upon insects and insect larvse. 



