146 ANURA 



CHAP. VI 



type. In fact there is little left which is primitive, but much 

 that is very specialised and highly developed in the Aglossa, 

 mostly in adaptation to their absolutely aquatic life, to which they 

 must however have taken very early. They are in a position 

 somewhat analogous to the Ratitae among Birds, which are like- 

 wise an old group, although many of their most striking features 

 have been acquired secondarily. 



Xenopus s. Dactylethra. The upper jaw is furnished with 

 teeth. The ilia are attached to the ninth vertebra. The pupil is 

 round. The terminal phalanges are pointed. The fingers are 

 free, the toes broadly webbed, and the first three are covered with 

 sharply pointed, horny, black -brown nails, a feature w^hrch is 

 alluded to by the alternative generic names. A cutaneous 

 tentacle projects from below the eye and naturally invites com- 

 parison with the tentacle of the Apoda and of Urodela. The 

 skin is smooth, rich in mucous glands, besides certain tube- 

 like apparatuses, possibly sensory, which are scattered over the 

 body, especially on the head, and form a conspicuous series of 

 white dots along the dorso-lateral line, from the eye to the vent. 

 The general colour of the upper parts is olive brown, mottled 

 darker, while the under parts are whitish. The female has 

 three cutaneous flaps closing the vent. The male develops black 

 nuptial brushes along the inner side of the fingers. There are 

 several species, all African (Ethiopian). 



X. laevis, ranging from the Cape to Abyssinia, is distinguished 

 by the absence of a metatarsal spur. The tentacle is very short. 

 Size about o inches. X. muelleri of Zanzibar and Benguella, 

 is smaller. The tentacle is conspicuous, as long as the diameter 

 of the eye. The inner metatarsal tubercle carries a sharp claw. 

 X. calcaratus of tropical West Africa is only 2 inches long, and 

 has strong metatarsal claws, short tentacles and very minute eyes. 



The habits and oviposition of the " Clawed Toad " have been 

 described by Leslie.^ The Boers call it " Plathander," i.e. flat 

 hand. Entirely aquatic, it rests floating in tlie water, with the 

 nostrils exposed, and leaves the water only if it has to change the 

 locality on account of drought or scarcity of food. The pairing 

 takes place, at least at Port Elizabeth, in the early spring, i.e. in 

 the month of August. The only sound which is emitted is heard 

 during this time, a very slight and dull tick-tick, audible at only 



1 P.Z.S. 1890, p. G9. 



