87 



essentials to revival from torpidity. The toad and 

 the lizard found sealed up in rocks, and the repose 

 of seeds under ground for a long extended period, 

 are merely an extension of the same principle, dis- 

 played at regular intervals every year, in the sleep 

 of the tortoise, hedgehog, dormouse, marmot, and 

 others, or in the insect and reptile world ; or the 

 repose of vegetation in the bud. The erinaceus 

 europeuSj or hedgehog, wraps itself up most curiously 

 in a ball of hay, with which it may be supplied ; the 

 intertexture of the fibres is remarkably close, and the 

 exterior surface quite smooth. We once had a tame 

 hedgehog, and its habits a good deal resembled 

 those of our dormice: it took its food always by 

 night. 



Dr. Reeve, in his " Essay on the Torpidity of Ani- 

 mals," has classed the phenomena of torpidity under 

 the following heads : 



I. The temperature of hybernating animals is dimi- 

 nished. 



II. The circulation of the blood becomes slower. 



III. The respiration is less frequent, and sometimes 

 entirely suspended. 



IV. The action of the stomach and digestive organs 

 is suspended. 



V. The irritability and sensibility of the muscular 

 and nervous powers are diminished and suspended. 



On each of these a few remarks will be made, to 

 preserve a somewhat arranged form : the causes of tor- 

 pidity may also be glanced at, and general deductions 

 made. 



I. Mr. Hunter ascertained that the temperature of 

 a hedgehog, at the diaphragm, in summer, was 97 

 Fahrenheit, when the thermometer in the shade was 

 78; when the air was 44, the animal became torpid, 



