PELOBATES. 201 



omata, a South American Cystignathoid, of likewise 

 nocturnal and burrowing habits, specimens of which 

 have often been kept in confinement in this country; 

 an important difference being, however, that a large 

 Ceratophrys is able to inflict a very painful bite on the 

 finger of the unwary. 



This Batrachian appears in the daytime only during 

 the breeding season, which takes place in March and 

 even as late as May* in Italy, between the end of 

 March and the beginning of May in Central and 

 Northern Europe, stray pairs occurring exceptionally 

 as late as the 21st of July, according to an observation 

 made by Prof. Van Bambeke at Ghent, Belgium, in 

 1875. At the time of pairing, at which pools or deep 

 ditches are resorted to, the males, much more nume- 

 rous than the females, utter under water a mono- 

 tonous, constantly repeated note — clock- clock, clock- 

 clock-clock, — produced by alternately shifting the air 

 backwards and forwards from the capacious lungs 

 into the buccal cavity. The female, which answers 

 by a sort of grunt or a deep tock-tock-tock, is seized 

 round the waist, and the eggs are expelled, more or 

 less rapidly, either immediately or within a few days. 



The length of the larval life varies considerably; as 

 a ride, the final transformation takes place from the 

 beginning to the end of summer, but several cases of 

 larval hibernation have been observed by Pfliiger and 

 Kollmann. 



Eggs. — The contents of the two oviducts fuse in the 

 cloaca, and are expelled in a thick band 15 to 20 mm. 

 in diameter when swollen up, in which the ova are 

 irregularly disposed at small interspaces. These 

 bands, which have a strong smell of fish, are twisted 

 round weeds by the female as they are laid. The ova 



* According to Spallanzani, who described the oviposition in a pair 

 brought to him in May, 1780, by a fisherman at Pavia, and who 

 received afterwards other pairs of the same species (CEuvres de 

 Spallanzani, III, ' Experiences pour servir a l'histoire de la Genera- 

 tion,' Pavie, 1787, p. 137). As Crivelli and Camerano have shown, 

 Spallanzani was the first after Posel to observe this curious Batra- 

 chian, which was not rediscovered in Italy until ninety years later. 



