MONOGRAPH OF THE GENUS PERIPATTJS. 439 



group, once widely diffused, 1 and probably rich in species and 

 genera, and closely related to the ancestors of living Arthropoda. 

 It probably has owed its preservation, as so many of the survivals 

 of ancient types seem to have done, to the peculiar habits of life 

 which are shared by all the living members of the class, viz. 

 the habitual avoidance of the light of day, and the habit of 

 seeking the obscurity and protection afforded by the spaces 

 beneath stones and beneath the bark of trees. 



Peripatus, though a lowly organised animal, and of re- 

 markable sluggishness, with but slight development of the 

 higher organs of sense, with eyes the only function of which 

 is to enable it to avoid the light — though related to those 

 animals most repulsive to the aesthetic sense of man, animals 

 which crawl upon their bellies and spit at, or poison, 

 their prey— is yet, strange to say, an animal of striking 

 beauty. The exquisite sensitiveness and constantly changing 

 form of the antennae, the well-rounded plump body, the eves 

 set like small diamonds on the side of the head, the delicate 

 feet, and, above all, the rich colouring and velvety texture 

 of the skin, all combine to give these animals an aspect of 

 quite exceptional beauty. Of all the species which I have 

 seen alive, the most beautiful are the dark green indi- 

 viduals of Capensis, and the species which I have called 

 Balfouri. These animals, so far as skin is concerned, are 

 not surpassed in the animal kingdom. The drawing on 

 PI. I. is from one of the dark green specimens of Capensis. 

 Clever as the drawing is, the artist has failed to catch the 

 exquisite velvet of the skin ; but this could hardly be expected 

 in a lithograph. I never shall forget my astonishment and 

 delight when on bearing away the bark of a rotten tree-stump 

 in the forest on Table Mountain, I first came upon one of 

 these animals in its natural haunts, or when Mr. Trimen 

 showed me in confinement at the South African Museum a fine 

 fat, full-grown female, accompanied by her large family of thirty 

 or more just-born but pretty young, some of which were 



1 That the class had once a world-wide diffusion is indicated by the wide 

 and discontinuous distribution of the living species, 



