XVI MIMICRY IN ZUPAIA 511 
perforated as in Hrinaceus (it is not so in Gymnura and Hylomys), 
but on the whole it comes nearest to Hylomys. 
Fam. 2. Tupaiidae.—This family contains the genera 7upaia 
and Ptilocercus. Tupaia is Oriental in range, extending as far 
east as Borneo. There are a dozen or so of species, which are 
generally arboreal and have the outward aspect of Squirrels. It 
has been suggested that this is a case of mimicry, the animal 
gaining some advantage by its likeness to the Rodent. The 
name Tupaia, it should be added, means Squirrel, and the long- 
nosed Squirrel, Sciwrus laticaudatus, is so extraordinarily like it 
that “one has to look at the teeth” to distinguish them. 
Moreover, this Squirrel, like some Tupaias, lives largely on the 
ground among fallen logs. Zupaia resembles a Lemur in the 
complete orbit. The dental formula is 12 C+ Pm3 M3=3 
The sublingua, too, is stated by Garrod to be like that of 
Chiromys. There is a minute caecum in 7” belangeri, none in 
T. tana. 
Ptilocercus* has a pen-like posterior portion to the tail, a 
modification which is found in other groups of animals. The 
tail of certain Phalangers, for instance, shows this same modi- 
fication. The rest of the tail is scaly. The animal, as was 
pointed out by Dr. Gray,? looks very much like a Phalanger. 
The orbit is entire as in Tupaia. The fingers and toes are five. 
The one species, called after Sir Hugh Low, G.C.M.G., P. low, is 
a Bornean animal. 
Fam. 3. Centetidae.—This family is entirely confined to the 
Island of Madagascar. It includes some seven genera. The best- 
known genus is Centetes. C. ecaudatus, the Tanrec, Tenrec, or 
Tendrac, is an animal a foot or so in length, without a tail, and with 
forty-four teeth.? The immature animal is so different from the 
parent as to appear quite a different form. It has three narrow 
rows of spines along the back, which do not wholly disappear 
until the permanent dentition has been acquired. Even then 
the hairs are of a rather spiny character, particularly those upon 
the back of the head, which are erected when the animal is 
1 «‘Notes on the Visceral Anatomy of the Tupaia of Burmah,” Proc. Zool. Soe. 
1879, p. 301. 
2 Proc. Zool. Soc. 1848, p. 23. 
3 I quote Woodward, Proc. Zool. Soc. 1896, for this dentition. The fourth 
molar of the lower jaw is not always present. It comes late, and only o/d animals 
possess it. 
