CHAMBERS'S INFORMATION FOR THE PEOPLE. 



sylvaticits), and the Common Mouse (M. musculus) 

 are British species, and are too well known to 

 require any description. A great number of 

 species exist in different parts of the world, differ- 

 ing little from each other. Belonging to the same 

 family are the Lemmings or Scandinavian Rats 

 (Myodes lemmus), which are remarkable for their 

 occasional migrations in immense bodies. They 

 are stated to advance in a straight line, regard- 

 less of rivers and mountains ; and while no in- 

 surmountable obstacle impedes their progress, they 

 devastate the country through which they pass. 

 The Hamsters (Cricetus) are nearly allied to the 

 rats, but their tail is short and hairy, and they 

 have cheek-pouches, in which they can stow away 

 grain for transport to their nests. They abound 

 in Asia, but one species is found in the sandy 

 plains of the north-east of Europe. The Voles 

 (Anicola), including the Short-tailed Field Mouse 

 (A. agrestis\ and the Water Rat (A. amphibia) are 

 forms intermediate between the Muridce and 

 Castoridce, 



Family 6. Dipodia, or Jerboas characterised 



Jerboa (Di 



by the enormous length of the hind-legs as com- 

 pared with the fore-limbs, which are very short, 

 and armed with claws with which they dig burrows 

 in which they I've, like most of the species of this 

 order. They live in troops, and inhabit Russia 

 and North America, They hop along on their 

 hind-legs much after the manner of a kangaroo. 



Family 7. Myoxida represented by one British 

 species, the well-known Dormouse (Myoxis avel- 

 lanarius), which must not be confounded with the 

 true Mouse, nor with the Shrew-mouse. 



Family 8. Sciuridce, or Squirrel tribe. The 

 characters and habits of the Common Squirrel 

 (Sciurus vulgaris) are too well known to require 

 description. The Pteromys, or Flying Squirrel, 

 is aided in leaping from tree to tree by an ex- 

 tension of the skin of the flank between the fore 

 and hind legs, which serves as a parachute. It 

 is an inhabitant of Southern Asia and Polynesia. 

 The Marmots (Arctomys) differ from the squirrels 

 in being fitted for living on the ground, and even 

 in burrows beneath it. A remarkable species is 

 the A. ludovicianus, or Prairie Dog, or Barking 

 Squirrel, so called because its bark resembles that 

 of a small dog. It lives in great troops in im- 

 ir.ense burrows on the plains of the Missouri. 



188 



They are connected with the former tribe, how- 

 ever, by an elegant little animal termed the 



Flying Squirrel (Pteromys volucella). 



Ground-squirrel (Tamias), partaking of the habits 

 of both : this is a native of Eastern Europe. Like 

 the Dormice, all the members of this family pass 

 the winter in cold climates in a state of lethargy. 

 The rodents of the first, second, and third families 

 are destitute of clavicles, while the remaining 

 families possess them. 



ORDER 9. Insectivora are small animals, sub- 

 sisting chiefly on insects and vegetable substances. 

 Their molar teeth are provided with numerous 

 small cusps, suited for bruising insects. They 

 are all nocturnal and subterranean in their 

 habits, and most of them spend the winter in a 

 state of sleep. Clavicles are present in the entire 

 order. 



Family i. Erinaceidce (Hedgehogs). These 

 animals are called Hedgehogs because they prefer 

 the roots of hedges as their hiding-places, and 

 from a superficial resemblance which they bear 

 to pigs. Nature has provided them with a bristly 

 coat of armour, which, by strong cutaneous muscles, 

 they can draw over every part of the body, or 

 every part which is accessible, so as effectually 

 to protect themselves from their enemies. They 

 roll themselves up into a ball at the approach of 

 danger. They live on fruit and the eggs of small 

 birds, and are torpid in winter. Our only British 

 species is the Erinaceus Europceus, which is too 

 well known to require description. 



Family 2. Talpidce (Moles) live chiefly under- 

 ground, feeding on insects, worms, and roots. 

 Their feet, which are provided with strong curved 

 claws, are admirably adapted to their subterranean 

 mode of life. From the smallness of their eyes, 

 which are scarcely perceptible, it was long con- 

 sidered that the Moles were blind ; but it is now 

 ascertained that they are by no means deficient in 

 the sense of sight. Moles have no external ears ; 

 but, from the tympanum being large, their sense of 

 hearing is nevertheless very acute. The only British 

 species is the Common Mole (Talpa Europ&a'). 



Family 3. Soricidce (Shrews) are small animals, 

 having soft hair, well-developed eyes, and external 

 ears, and the feet are not adapted for digging. 



