230 



THE NATURE BOOK 



HIGHLY MAGNIFIED 

 CROSS SECTION OF 

 THE HEDGEHOGS 

 OUILL. 



are neatlv brushed back. He next rounds 

 his back and tucks his face, four feet, 

 and tail, together into his stomach. At 

 this stage, viewed from the side, he is 

 shaped like a nautilus, while the last 

 glimpse of his black nose and paws, with 

 their surround of hair, reminds one 

 curiously of a befrilled infant. Finally 

 he tightens up until he is practically 

 spherical, with nothing but quills visible, 

 and every quill pointing outwards. 



He now presents a defence which few 

 animals care to 

 engage, though it 

 is said that the 

 fox and badger 

 can pull him to 

 pieces (the badger 

 certainly could), 

 and I ha\-e known 

 a case of a re- 

 triever who habit- 

 ually ate Hedge- 

 hogs, spines and 

 all. and who even- 

 tually died of gas- 

 tric trouble induced by the consumption 

 of a particularly large specimen. The 

 injury was probably mechanical, as it 

 is not likely that ordinary Hedgehogs' 

 quills would defy a dog's digestion. 

 They can be considerably softened by 

 boiling water, while a few hours' soaking 

 in turpentine will reduce them to a 

 pulpy condition. Each quill, in fact, is 

 a single modified hair, so that, as a 

 general rule, we can find four different 

 kinds of hair in the Hedgehog — the quill, 

 the bristle, the coarse hair, and the fine 

 hair, whose diameters at their thickest 

 portion average i'2, -ii, -06, and -02 milli- 

 metres respectively. The bristles and the 

 coarse hairs are remarkable for the small 

 size of their pith in comparison with their 

 shell, while in the fine hairs the pith can 

 hardly be traced at all. A tame Hedge- 

 hog enjoys being stroked, and will lay his 

 quills back for that purpose. 



I do not think that the Hedgehog 

 deliberately uses his quills for any pur- 

 pose other than defence. The quaint 

 appearance which he sometimes presents 

 in the spring, owing to the quantity of 

 nest material sticking to him, is due 

 simply to the movements which he has 

 made in settling down in his nest for the 



winter, and in waking up from his long 

 sleep. The idea that he can climb trees 

 and spike the apples need only be men- 

 tioned to be dismissed. 



Yet, considering his natural disad- 

 vantages of build, he is no mean climber, 

 and I have known one escape from a 

 first-floor room by climbing from the 

 floor to a chair, from the chair to a table, 

 from the table to a window-sill, and 

 thence to the branch of a tree which 

 came close up to the wall. He negotiated 

 part of this branch successfully, then lost 

 his balance and fell, but waddled off 

 triumphant. 



The phenomenon of hibernation which 

 I touched on in the case of the Dormouse 

 is displayed even more markedly in the 

 Hedgehog. His torpor lasts from Novem- 

 ber to March, and is, I think, normally 

 unbroken. I have had the opportunity 

 of making daily observations on the hiber- 

 nation of three individuals, and I am 

 certain that in these cases the animals 

 remained torpid from the time they 

 turned in until the time they turned 

 out. There are, however, many instances 

 recorded of Hedgehogs roaming at large 

 during hard weather, and I have more 

 than once myself encountered them in 

 snow. 



The Hedgehog possesses " hibernating " 

 glands. The nature and function of these 

 are uncertain, but it seems generally agreed 

 that they attain their greatest develop- 

 ment in the autumn, and atrophy in the 

 summer. We shall have something similar 

 to consider in the case of the Shrew Mice. 

 So far as the Hedgehog is concerned, the 

 matter has been ably dealt with by Dr. 

 Carlier.* Among the interesting facts 

 he brings to light, is the absence of sweat 

 glands and sebaceous glands (the former, 

 of course, implying an opening to the air) 

 on the quill surface of the Hedgehog's 

 body, and the migration of armies 

 of phagocytes at the commencement of 

 hibernation towards those portions of 

 the animal's body, mostly situated in 

 the alimentary canal, which are, at this 

 critical period, dangerously exposed to 

 assaults of bacteria. 



If we consider the normal position of 

 the hibernating Hedgehog — a tightened 



*" Contributions to the Histology of the Hedge- 

 hog." Edinburgh, 1892. 



