79? THE AMERICAN NATURALIST. [Vor. XXXIV. 
very early, and are soon able to escape from the muddy fluid; 
thus, by accelerated metamorphosis, the chances of succumb- 
ing because of drought are lessened. 
Lythodites latrans, which lives in fissures of limestone 
precipices of western Texas, is also supposed to deposit its 
eggs in pools of rain water. 
The eggs of Phryniscus nigricans, in Paraguay, are laid 
singly, in temporary pools in grassy ground. “The eggs and 
larvee do not seem to differ in any great degree from those of 
Rana. There is, however, a very large yolk plug, which remains 
evident after the closure of the neural groove.” The develop- 
ment is very rapid, and, within twenty-four hours after segmen- 
tation begins, the tadpoles are hatched and wriggling about. 
They are probably washed into deeper pools. 
Another case of rapid development is that of Paludicola 
fuscomaculata, also found in Paraguay. It spawns in January 
in shallow pools, and the eggs float on the surface. They meas- 
ure I mm., are unpigmented, and have very little yolk. The 
tadpoles hatch within eighteen to twenty-four hours after seg- 
mentation begins, and hang in the water from the floating froth. 
* Many of the processes of development are blurred and, as it 
were, hurried over. The external gills never reach a high 
state of development." 
Eggs which are thought to develop like those of Paludicola 
are said by the natives of Paraguay to belong to the frog called 
by them * Po it," more scientifically Eugystoma ovale. Eggs 
and larve are found in froth in holes in the ground, beneath 
fallen tree trunks. The nests * were a most ingenious CON- 
trivance for collecting water and keeping the eggs and larvae 
at least moist between the storms of the wet season. They 
were always found within the forest belts which lay on the 
highest ground." The larva “would exist for a very long 
time in a small quantity of water without increasing in size, 
but when removed to a tank they grew enormously and Very 
soon left the water." 
A curious indifference to water has been observed 1 
case of Sea bombifrons, near Market Lake, in Idaho. 
tadpoles, still “in the free-swimming condition," but en 
n the 
The 
tirely 
