xxii. 7 



PANGOLINS 



60 1 



moving very slowly among the branches, which they come to resemble 

 closely by the growth of blue-green algae in special grooves in the 

 hairs. Their upside-down posture has led to many changes from the 

 typical mammalian organization, including, it is said, a reversal of the 

 usual mechanism for maintaining posture. When a normal mammal 

 is decerebrated its legs assume a pillar-like extensor rigidity, because 

 of the overaction of the reflexes of standing. A decerebrate sloth is said 

 to show the opposite, flexor rigidity. 



7. Order Pholidota : pangolins 



The pangolins or scaly ant-eaters, Manis (Fig. 381) of the Old World 

 (Africa and Asia) have many features superficially like those of the 

 New World ant-eaters and the groups 

 may be remotely related. Unfortu- 

 nately nothing is known of the fossil 

 history of Manis and its position 

 among the unguiculates is therefore 

 provisional. The body is up to 5 ft 

 long, covered with horny epidermal 

 scales, interspersed with hairs. The 

 absence of teeth, the elongated snout, 

 long thin tongue, simple stomach, 

 reduced ears, and long claws are all 

 features found in the other ant-eaters. 

 Rods of cartilage extending backwards 

 from the xiphisternum have been 

 compared with the abdominal ribs of 

 reptiles, but are probably a special 

 development, connected with the pro- 

 trusion of the enormous tongue, which 

 is carried in a special sac and operated 



by muscles attached to the xiphisternal processes. The animals are 

 macrosmatic, with small eyes. The brain is very small, but the hemi- 

 spheres are folded. The placenta is diffuse and epithelio-chorial, with 

 a large allantois and a yolk-sac persisting until birth. Evidently the 

 pangolins preserve many very ancient mammalian features. There are 

 various species of Manis; some live in open savannah, others are able 

 to climb trees. All are nocturnal and eat ants and termites. 



Fig. 381. Black-bellied tree pangolin, 

 Manis. (From photographs.) 



