AMPHIBIANS—GOIN 435 
with a sudden noise. The male then moves his legs around, entwining 
the eggs about his legs. He carries them for several weeks, until the 
tadpoles are about ready to hatch, at which time he makes a brief 
visit to a pool where no other tadpoles are present. Here he deposits 
the eggs; the little tadpoles hatch out and finish their development 
as tads in the pool. 
Bombina maxima, the yellow-bellied toad, breeds in the water. The 
male clasps the female just above the front of the hind limbs and the 
eggs are laid in small masses which, instead of being wrapped around 
the legs of the male, sink to the bottom or come to rest suspended on 
submerged vegetation. Here they lie until the eggs hatch. 
Rhinophrynidae—The Mexican burrowing toad, Rhinophrynus, 
exhibits an aquatic courtship, the males grasping the females in front 
of the hind legs. The eggs are then deposited in the water where they 
hatch out into aquatic larvae which later undergo metamorphosis. 
Leptodactylidae——The two abundant genera of New World lepto- 
dactylids, Leptodactylus, the nest-building frogs, and Lleutherodac- 
tylus, the robber frogs, have rather uniform life histories among 
themselves. The species of Leptodactylus build frothy nests in or 
near bodies of water. The eggs are deposited and hatch within these 
nests. The larvae have very slim bodies and make their way through 
the nest to the adjacent water. While there is some variation in larval 
form among the different species, in general throughout the genus 
there is agreement of nest form and larval habits. A few leptodac- 
tylids have become more terrestrial. Z. nanus scoops out a small 
basin in the earth at a site some distance from the water. The froth 
and eggs are deposited in this basin which is then roofed over with 
mud. A tiny aperture is left at the top through which the young 
escape after metamorphosis. 
Fleutherodactylus lays its eggs on land. Here, about sunrise in 
the morning, generally under stones or logs or similar cover, the 
female deposits her eggs while clasped by the male who fertilizes them 
as they are deposited. These eggs go through direct development and 
at hatching the little froglet is a miniature replica of the adult. 
Life histories of Paludicola and Hupemphix are similar in pattern 
to that characteristic of Leptodactylus. Zachaenus, like L. nanus, lays 
its eggs in an earth basin, but the basin is not roofed over. The 
young, however, complete metamorphosis in the basin as do the young 
of L. nanus. 
In the Australian Helezoporus eyrei, the eggs are laid in a frothy 
mass of jelly underground in the spring of the year. Development 
proceeds within the egg until the external gills have been lost and 
the gill covering developed. Hatching seems to depend on the nest 
being flooded. 
