DESCRIPTION.—To be distinguished from the two preceding species by the greater number of longitudinal rows of scales, M. pentadactyla having from eleven to thirteen, M. aurita from fifteen to eighteen, and M. Javanica nineteen. Taking the number of scales in the longitudinal mesial line from the nose to the tip of the tail in M. pentadactyla, it is forty-two; in aurita forty-eight to fifty-six; in Javanica as high as sixty-four; on the tail the scales are: M. pentadactyla, fourteen; M. aurita sixteen to twenty; M. Javanica thirty.
I am indebted to Dr. Anderson's 'Zoological and Anatomical Researches' for the following summary of characteristics:—
"M. pentadactyla by its less heavy body; by its tail, which is broad at the base, tapering gradually to a point, and equalling the length of the head and trunk; by its large light olive-brown scales, of which there are only from eleven to thirteen longitudinal rows on the trunk, and a mesial line of fourteen on the tail; and by its powerful fore-claws, the centre one of which is somewhat more than twice as long as the corresponding claw of the hinder extremity. M. aurita is distinguished from M. pentadactyla by its less heavy body; by its rather shorter tail, which has less basal breadth than M. pentadactyla; by its smaller and darker brown, almost black scales in the adult, which are more numerous, there being from fifteen to eighteen longitudinal rows on the trunk, seventeen rows being the normal number, and sixteen to twenty caudal plates in the mesial line; and by its strong fore-claws, the middle one of which is not quite twice as long as the corresponding claw on the hind foot.
"M. Javanica is recognised by its body being longer and more attenuated than in the two foregoing species; by its narrower and more tapered tail; by its longer and more foliaceous or darker olive-brown scales, of which there are nineteen longitudinal rows on the trunk, and as many as thirty along the mesial line of the tail; and by the claws of the fore-feet being not nearly so long as in M. aurita, and being but little in excess of the claws of the hind-feet."
[APPENDIX A.]
FAMILY MYOXIDÆ—THE DORMICE.
These small rodents approximate more to the squirrels than the true mice; but they differ from all others intestinally by the absence of a cæcum. They have four rooted molars in each upper and lower jaw, the first of each set being smaller than the other three, the crowns being composed of transverse ridges of enamel. In form they are somewhat squirrel-like, with short fore-limbs, and hairy, though not bushy, tails. The thumb is rudimentary, with a small, flat nail; hind-feet with five toes.
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Dentition of Dormouse (magnified). |