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Pholidota

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PHOLIDOTA The pangolins (q.v.) or scaly ant-eaters of Africa and tropical Asia were at one time associated with the Edentata mainly on account of their likeness to the South American ant-eaters in the absence of teeth, the weakness of the jaws, the enlargement of the salivary glands, and the length of the vermiform, extensile tongue ; and to the armadillos in the possession of a hard dermal exoskele ton. But the resemblances to the former group are adaptive and due to similarity of diet and the exoskeleton is of a totally differ ent type from that of the armadillos, since it consists of large, erectile, overlapping horny scales, composed of cemented hairs, there being no trace of bony matter in the skin. They show, in deed, no resemblances to the edentates of any systematic im pc tance and differ from them fundamentally in many characters, such as the absence of extra articular processes in the spinal column, the presence of a bicornuate, instead of a globular, uterus, of a diffused, non-deciduate, instead of a dome-shaped deciduate, placenta, etc.

The head is short and conical, with functionless facial vibrissae and a moist normal rhinarium as in Myrmecophaga; the ear some times has a distinct pinna but may be represented by a vertical slit only. The legs are short but the feet vary in structure according to habit. The fore foot has five toes of which the second, third and fourth are always armed with large claws, the largest being on the third; the first and fifth digits are very variable in size and are usually small clawed. The hind foot also has five toes which vary in size and in the size of the claws. The tail is also variable, sometimes being excessively long and prehensile, sometimes com paratively short and forming, with the hind legs, a kind of trip odal support ; at other times it is intermediate in structure. The anus and external genitalia are situated close together on an eminence formed mainly by the enlarged anal glands, and the anus is sunk in a depression into which the ducts of the glands open; both the penis and clitoris are quite small.

Pangolins range in Asia from north India and south China to Ceylon and Borneo and in Africa from Sierra Leone and Uganda to the Cape. There are several different kinds. Some are almost entirely arboreal, some purely terrestrial, while others which live in the main on the ground also climb trees as well. Otherwise their habits are very similar. They feed mostly on termites, ripping open the nests of these insects with the strong claws of the fore feet. Their means of defence are the emission of a repulsive odour from the large anal glands and rolling into a compact ball with the hard, often sharp, erected scales presented to the enemy and protecting the soft-skinned hairy underside of the body from injury.

There are several species and genera, all referred to the family Manidae. But this is divisible into three sub-families. In the Asiatic species, the Maninae, the hinder end of the sternum or breast-bone is shaped like the blade of a spade, having a convex posterior edge and two forwardly directed spiniform angles. To this group belong the north Indian and Chinese eared pangolin (Manic pentadactyla), the Indian and Ceylonese thick-tailed pan golin (Phatages crassicaudata) and the Javanese and Bornean pangolin (Paramanis javanica), which differ in many external characters.

In the African pangolins the end of the breast-bone is pro longed into two long rods running back to the posterior ribs. There are two well defined sub-families differing in habitat and correlated structural characters. The Smutsiinae, containing the genus Smutsia with the two species temminckii and gigantea, are terres trial with the feet and tail adapted for ground life ; and the Phatag inae, containing the two small west African pangolins, Phatag inus tricuspis and Uromanis longicaudata, which differ from all other pangolins in being adapted to arboreal life, their tails being exceedingly long and prehensile, and the feet with only four functional toes, the upper side of the fore foot being without scales.

Extinct Pangolins.

Bones of a large pangolin, indistinguish able from the African giant pangolin, have been found in a cave in Madras; in Lower Pliocene deposits of Samos occur Palaeo manis and earlier still are Leptomanis and Necromanis from the Upper Eocene phosphorites of Quercy.

pangolins, pangolin, feet, glands, species, size and claws