REPRODUCTION 193 



movements of his toes, she stretches out her hind limbs, he places 

 his between them, bent at angles at the knees, the tarsi erect and 

 pressed close together, thus forming a receptacle in which the 

 eggs are suddenly extruded. The yellow eggs, as if threaded 

 together by elastic filaments continuous with the gelatinous 

 capsules, form a large mass, two to four layers of about ten 

 eggs, in this receptacle. The very moment the eggs are pro- 

 duced, the male unclasps the waist of the female and shifts his 

 hold to the base of the head ; the body then stretched out, but 

 the legs remaining in the same position as before, fecundation 

 commences ; it takes place in two or three emissions at short 

 intervals. After a few minutes' rest, the male proceeds to at- 

 tach the strings of eggs to his legs, by passing the latter into the 

 egg-mass and then folding them against his body. There 

 they remain until hatched. Thus laden, and yet so little im- 

 paired in his movements as to occasionally resort again to 

 hymen during the nursing period, and successfully add on a 

 second burden, the male retires to his usual retreat, in a hole 

 in the ground, or between the stones of some old wall, but go- 

 ing about at night in order to feed himself and to keep up the 

 moisture of the eggs, even resorting to a short immersion in 

 the water during exceptionally dry nights. The development 

 in the egg takes about three weeks. At the expiration of this 

 period, he enters the water with his burden ; the larvae, in the 

 full tadpole condition, and limbless, measuring fourteen to 

 seventeen millimetres, bite their way through the tough envelope 

 or egg-string, which is not abandoned by the father until all 

 the young are liberated. The rest of the development does 

 not differ from that of other frogs. 



The rosary-like string -contains about twenty to fifty eggs, 

 which, considering the small size of the frog (forty to fifty mil- 

 limetres from snout to vent) are remarkably large, measuring 

 three and a half to five millimetres in diameter. When first 

 laid the eggs are nearly spherical, but they soon acquire a 

 more oval shape. Through the transparent capsules the 

 whole development can be easily followed. An enormously 

 large vitelline sac is present, and the embryo is provided with 

 uncommonly long, unpigmented, branched external gills, one 

 only on each side, which are absorbed and replaced by 

 internal ones before the larvae are hatched, 



13 



