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POPULAR SCIENCE MONTHLY. 



nants of the mass laid with the egg, is as yet undecided. The part of 

 the skin of the back not taken np by these pits rises up in small 

 papillge, and thus each pit is closely surrounded by a ring of papillae. 

 From 40-114 pits are formed, and 60-70 young are developed. 



Each egg thus develops inside a diminutive womb-like chamber, 

 on the back of the mother, but as yet we do not know whether the 

 mother supplies any nutriment to the young while it is in this pro- 

 tecting chamber; the arrangement of lymph and blood vessels in the 

 skin of the mother and the organization of the young, however, raise 

 the question whether this may not be the case. In each pit the young 

 tadpole lies with its back toward the roof and its belly downwards. For 

 awhile it has a large yolk-bag, or enlargement of its belly, full of nutri- 

 ment and richly supplied with blood vessels; also a tail. This tail is 

 very large, and seems to be of no use, unless it may function as a 

 breathing organ, as in the frog of Guadaloupe, mentioned above. 

 Another peculiarity of these favored tadpoles is that they obtain their 



Fig. 11. 



Fig. 12. 



front legs at a very early period, before their gills grow out; and thufl, 

 for a long time, appear as four-legged creatures, with most imposing 

 tails, as represented in Fig. 11. 



In this condition they break off the roofs of their little houses and 

 each, like a baby kangaroo from its mother's pouch, peers out into the 

 world with goggle eyes and ready hands. For nearly three months 

 (eighty-two days) the mother is burdened like Sindbad, till the young 

 toads jump out of their cradles and go free to shift for themselves. 



Every Surrinam toad is thus launched upon its individual voyage 

 of contest for food as a complete but small toad, and, though it had 

 the outward symbols of tadpole life — gills and a tail — it never lived a 

 tadpole life, with its dangers from the drying of ponds, and the chances 

 of being swallowed alive as so many tadpoles are. Our common tad- 

 poles may, from one point of view, be regarded as chiefly feeding 

 phases, like the caterpillar that eats and eats to pass through the inac- 

 tive chr}'salis stage to the complete butterfly life. Tadpoles are phases 

 of the frogs' lives, when almost anything can be eaten, and when there 



