SUPPRESSED METAMORPHOSIS. 485 
As an example of a suppressed metamorphosis, due ap- 
parently to a radical difference in the physical environment 
of the animal, may be cited the case of a tree-toad in the 
island of Guadaloupe. There are no marshes on this island, 
consequently in a species of Hylodes the development of 
the young is direct; they hatch from the eggs which are 
laid under moist leaves, without tails, and are otherwise, ex- 
cept in size, like the adults. On the other hand, a tree-toad 
of the island of Martinique (Hylodes Martinicensis, Fig. 
436) has tadpoles, which it carries on its back. The female 
of Nototrena marsupiatum Dumeril and Bibron, of the 
Andes, has a marsupium or sac on its back in which the 
young are carried. The Wotodelphys 
of South America has similar habits ; 
for example, the female Opisthodel- 
phys (Notodelphys) ovifera has a dor- 
sal sac a centimetre deep in which 
the eggs are carried. In the young 
of this and of Gastrotheca also of 
Central America, Peters found traces 
of external gills. The Pipa, or Suri- 
nam toad (Pipa Americana Laurent), 
which has no tongue, neither teeth in SS (4 
the upper jaw, has similar breeding fig. 43¢—‘rne Martinique 
habits. In this interesting toad the Tree-toad carrying the young 
young, according to Prof. Wyman, 
are provided with small gills, which, however, are of no 
use to them, as the tadpoles do not enter the water, but are 
carried about in cavities on the back. The eggs are placed 
by the male on the back of the female, where they are 
fertilized. The female then enters the water; the skin 
thickens, rises up around each egg and forms a marsupial 
sac or cell. The young pass through their metamorphosis 
in the sacs, having tails and rudimentary gills; these are 
absorbed before they leave their cells, the limbs develop, 
and the young pass out in the form of the adult. 
The toad (Bufo lentiginosus Shaw) is exceedingly useful as ‘ 
a destroyer of noxious insects. It is nocturnal in its habits ; 
is harmless, and can be taken up with impunity, though it 
