Jenyns' Natural History. 1855 



" On the 15th of June, 1830, I had a very large female of the black sort brought 

 to me, which had been killed in the next village : it was gravid at the time, and, on 

 opening it, I found eight young within, perfectly formed, and apparently quite ready 

 for exclusion.* 



" I once at Ely found a small specimen of this black variety, measuring not quite 

 five inches from the nose to the root of the tail, lying dead on the ground beneath the 

 nest of a white owl. Like shrews, which are also often found at the foot of their nests, 

 along with their casts, this rat appeared to have been caught and brought home by 

 the parent owls to their young, but afterwards rejected." — p. 76. 



Malformation in Rabbits' Teeth. — " Instances of the wild rabbit have occasionally 

 been met with at Bottisham, in which the fore-teeth had grown to so great a length as 

 to be rendered wholly unfit for the purposes they are intended to serve. This malfor- 

 mation is the result of the cutting edges of these teeth not being sufficiently worn down 

 by use, or to the degree that they are in healthy individuals, and to supply which loss 

 the teeth themselves are provided with the power of growth. But the original cause of 

 the evil may vary in different cases. Thus, it may be due to one pair of incisors, or 

 one single incisor, being broken, or having fallen out; to too soft food; to a morbid 

 and too rapid secretion of the osseous matter of the tooth, which is constantly being 

 deposited at its root ; or to some slight derangement of the under-jaw, such as, for in- 

 stance, a dislocation of one of its condyles, whereby the incisors of that jaw would be 

 thrown out of their proper position, and their cutting edges could not be brought 

 fairly into contact with those of the opposite pair. In all these cases, either the attri- 

 tion of the teeth would be checked altogether, or their growth would be over-propor- 

 tioned to their abrasion by the acts of gnawing and feeding, and a preternatural elon- 

 gation of that part which is above the gums would immediately take place. It is ob- 

 vious that this diseased growth will be more or less rapid according to the degree of 

 influence exerted by the predisposing cause, and the length of time it has operated. 

 Perhaps, in the first stage of the malady, its progress may be very gradual, and not 

 much interfere with the usual habits of the animal ; but the teeth having once 

 attained such a length, that, under any circumstances, their edges cannot be brought 

 to act upon each other, their growth must be much more rapid, and ultimately prove 

 such an inconvenience as must often terminate in the starvation of the sufferer. 



" In one rabbit, preserved in the Museum of the Cambridge Philosophical Society, 

 the lower pair of incisors are so prodigiously developed as to turn completely over the 

 nose, and to measure in length, from the surface of the gum to their cutting edges, no 

 less than two inches and one-eighth ; their usual length in ordinary individuals being 

 only a quarter of an inch. In another rabbit, that occurred in this neighbourhood, 

 but which was not preserved, both pairs of incisors had very much exceeded their usual 

 length, there being also a great irregularity in their mode of growth. The lower pair, 

 when viewed together, assumed the shape and appearance of the letter V, diverging 

 from one another at the surface of the gum, and extending in opposite directions, to 

 the length of nearly an inch and a half : the degree of divergency observed in the 



* Mr. Jesse's " sort of mole, which partook very much of the appearance of a rat," 

 is no doubt referrible to this black variety of the water-vole. See ' Gleanings,' 

 &c. (2nd Ser.) p. 27. 



