202 ANURA CHAi'. 



like golil, and in other moods the whole upper surface is mottled 

 blue, green, and brown. My specimens often went into the 

 water and did not climl). The food is said to consist chiefly of 

 other small frogs in preference to insects. 



Xototrema differs from Hi/la in so far as the female has a 

 pouch on the back for the reception of the eggs. This bag is 

 formed \>y an infolding of the skin : it opens backwards in front of 

 the vent, it has a sphincter and is permanent, although it distends 

 to larger dimensions when in use. An initial stage of such a pouch 

 is possessed by Ifj/la goeldii (Fig. 38). The pupil is horizontal, 

 the tongue can be protruded but little ; the tympanum is free, 

 and the adhesive discs of the fingers and toes are well developed. 

 These " marsupial frogs," of which about half-a-dozen species are 

 known, live chiefly in the tropical forest-region of South America, 

 notably from Peru to Venezuela. 



K. marsvpiatum is green with darker blue-grten spots, or 

 with longitudinal patches which are each surrounded by a 

 whitish or yellow seam of little dots. The limbs have cross-bars. 

 Total length about 2-^ to 3 inches. The eggs of this species 

 are comparatively small and numerous. The very small tadpoles 

 have no external gills, and escape from tlie pouch to finish their 

 metamorphosis in the water. 



JV. trstu(Uneum,aho\it 3 inches in k'ngtli, is of a uniform lead- 

 colour, but is lighter beneath. The skin of the back is studded 

 with stellate calcareous deposits, a peculiarity which is alluded 

 to in the specific name. 



X. oviferum is brown above, with darker patches on the sides 

 of the body and with cross-bars on the limbs. The last two 

 species and X. Jissijjcs of Brazil, near rernambuco, carry their 

 young in the pouch until the metamorphosis is completed. This 

 long nursing-period necessitates a great amount of food-y(»lk in 

 the eggs, and this enlargement in turn implies a considerable 

 reduction in their number. The female's load consists of about 

 fifteen eggs only, hut these are of a great size, namely one-eighth 

 of the lenu'th of the mother's bodv. 



X. piiipiuicv/in, in Venezuela, is a tiny creature. The female, 

 just one inch in length, carries only from four to seven eggs. It 

 looks then " as if it carried a sac filled with a few gioantic balls." 

 This species is further worthy of note on account of the opening 

 of the l)rood-pouch, which is a longitudinal slit, whence a kind 



