enabled to hold the female.' It is surprising- that tliese animals have 

 not acquired more strongly-marked sexual characters, for, though cold- 

 blooded, their passions are strong. Dr. Giinther informs me that 

 he has several times found an unfortunate female toad dead and 

 smothered from having been so closely embraced by three or four males. 

 Frogs have been observed by Professor Hoffman in Giessen fighting 

 all day long dui-ing the breeding season, and with so much violence 

 that one had its body ripped open. 



" Frogs and toads offer one interesting sexual difference, namely, 

 in the musical powers possessed by the males ; but to speak of music, 

 when applied to the discordant and overwhelming sounds emitted by 

 male bull-frogs and some other species, seems, according to our taste, 

 a singularly inappropriate expression. Nevertheless, certain frogs sing 

 in a decidedly pleasing manner. ^ Near Eio Janeiro I used often to 

 sit in the evening to listen to a number of little Hylee, perched on 

 blades of grass close to the water, which sent forth sweet chirping 

 notes in harmony. The various sounds are emitted chiefly by the 

 males during the breeding season, as in the case of the croaking of our 

 common frog. In accordance with this fact the vocal organs of the 

 males are more highly developed than those of the females. In some 

 genera the males alone are provided with sacs which open into the 

 larynx. For instance in the edible frog (Rrrna c-scidei/fa)^ the sacs 

 are peculiar to the males, and become, when filled with air in the 

 act of croaking, large globular bladders, standing out one on each side 

 of the head near the corners of the mouth. The croak of the male is 

 thus rendered exceedingly powerful, whilst that of the female is only 

 a slight groaning noise." 



In some Batrachians, e.g., the American Pipa, there is no tongue, 

 but all the South Indian tailless Batrachians possess a tongue, which is 

 attached in a different manner to that of the higher vertebrata, being 

 fixed in front between the rami of the lower jaw {Ojndlwglossa) and 

 frequently bifid or emarginate and free behind and capable of being 

 projected out of the mouth (fig. 2), and acting as an organ of prehension. 



Fig. 2. 



In some species, e.g., Rana diplosticta (pi. Y, fig. 3), the tongue has a free 

 conical prominence called the papilla on the middle of its upper surface. 



* Dr. J. Anderson has described the sexual characters of the male of Bufo sikkimensis, 

 Blyth, as consisting of "two plate-like callosities on each side of the thorax, thickly- 

 studded with minute dark-brown granules, such as occur on the same region in B. Hebir/i 

 and other Batrachia. Similar to these structures is the rough, almost sjDiny surface on the 

 upper aspect of the first and second fingers and on the inner margin of the third. The 

 female, as in other Batrachia, has no trace of these structui-es." Froc. Zool. Soc, 1871, p. 204. 



^ The male of the South Indian toad, Bufo melanostictus, occasionally emits a clear, sharp 

 musical note, which is not at all unpleasant. 



