The pairing and oviposition, and the manner in which the eggs are conveyed into the gular sac, have not yet been observed. Espada examined five males with young, the number of which varied from five to fifteen. In one male with eleven embryos the most developed tadpoles measured 13.5 mm. from the snout to the end of the tail, and they were lying within the chest of the father, the less advanced in the farther recesses of the bag. Three of the tadpoles had already completely-formed fore- and hind-limbs, while the arms were still hidden. The least developed were still globular, a proof that the eggs are conveyed into the bag. Another male with fifteen embryos looked as if it had gorged itself with the almost fully-formed tadpoles, which measured 14 mm. They were quite irregularly distributed, and nowhere {230}attached to the walls of the bag. None of them had horny jaw-armaments, and not even the smallest specimens showed any traces of gills, resembling in this latter character those in the female brood-pouch of _Nototrema_. The intestine of the tadpoles is short and thick, coiled up spirally and filled with yolk, certainly not with vegetable or other foreign matter. Consequently the entire development from the egg to the complete stump-tailed little creature is undergone within the pouch; and this, after the young have escaped, probably shrinks back to its original size and acts as a gular vocal sac. _Phryniscus._–About ten species of this tropical American genus are known; they extend from Costa Rica to Buenos Aires. They differ not inconsiderably in various details. The tongue is elliptical, entire, and free behind. The palate is smooth. The tympanic disc is absent. Fingers and toes more or less webbed, sometimes with swollen tips, without, however, forming adhesive discs. In a few species the first toe is quite indistinct. The male has a subgular vocal sac. The mouth is small, and there is a short snout. The general appearance varies much. _Ph. nigricans_ of Uruguay, etc., is stout and has very short hind-limbs; the skin of the upper parts is black, spotted with white, and covered with warts. Most of the other species are slender, with larger hind-limbs and a perfectly smooth skin, the coloration of which ranges from dull uniform brown, or black with crimson markings, to bright green with purple spots. The under parts are, as a rule, conspicuously coloured, a rare feature in Anura, the favourite colours being orange, yellow, or even crimson, with or without black patches.