_Engystoma_, with about five species in the Southern States, Central and South America, is the type-genus of the whole family, chiefly on account of priority of name. It is fairly characteristic in so far as the mouth forms a narrow, somewhat projecting snout; the precoracoids, the clavicles, and the omosternum are absent, the palate is devoid of teeth, the lining of the mouth forms a dermal ridge across the palate and another in front of the oesophagus, the tympanum is hidden, the sacral diapophyses are moderately dilated, and the tongue is elliptical and free behind. The pupil is vertical. The fingers and toes are free, ending in slightly dilated or blunt tips; the terminal phalanges are simple {232}and the hind-limbs are short. The male has a subgular vocal sac. The most northern species is _E. carolinense_, living in the Southern United States, concealed under the bark of fallen trees or in old fences. The skin is smooth, but forms a fold across the head, behind the eyes. The general colour is brown, with light, whitish dots on the under parts. Total length 1 inch. _Breviceps_ is a South African genus with three species. The coracoids are very strong and directed backwards, but so broadened that they form a long and strong symphysis, touching in front that of the precoracoids, which stand transversely and are well developed. The metasternum is cartilaginous and decidedly small. The sacral vertebra has much dilated diapophyses and is co-ossified with the coccyx. The general appearance is extremely stout and short, the head being almost drawn into the nearly globular body, and ending in a short snout with a small mouth-opening. The tongue is long and oval, not nicked, but slightly free behind. _B. mossambicus_ is about 2 inches long, and looks like an overstuffed round bag, out of which the short arms and legs project from the elbows and knee-joints only. The tarsus is provided with a strong horny, spade-like tubercle, which enables the creature to dig into the ground, and into the nests of termites, which seem to be its chief food. Peters found this species in enormous numbers, during the tropical rains, coming out of the ground, whither they withdraw again completely for the dry season. The skin is smooth, reddish brown above, with darker patches; the under parts are dull white, with a large black patch on the throat.