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ON THE SPAWNING OF BOMBINATOR PACHYPUS 

 AFTER TWO YEARS OF CAPTIVITY IN 

 ENGLAND. 



By J. L. Monk. 



The difficulty with which Batrachians are brought to breed 

 in confinement, whether kept indoors or in the open, is well 

 known to all who have attempted to study the habits of this 

 interesting class of animals. It is also generally believed that 

 when once the annual discharge of the genital products has been 

 interrupted by captivity, the individuals are for ever barren. 

 For example, the Xenopus Icevis in the reptile-house at the 

 Zoological Gardens bred in the year of their arrival, but in no 

 subsequent year could they be induced to do so. 



The case I have the pleasure of putting on record is therefore 

 a most interesting one. Some specimens of Bombinator pachypus, 

 captured by my friend Mr. Boulenger in Belgium in the early 

 spring of 1897, before the breeding season had set in, have been 

 kept in an aquarium for two years, when it was ascertained that, 

 although pairing repeatedly took place, no spawn was ever 

 deposited. Having placed them this spring in a small pond in 

 my garden at Forest Gate, they have, to my surprise and satis- 

 faction, paired and spawned under my eyes ; and I append some 

 notes on the observations I was able to make on this occasion, 

 which may be acceptable to the readers of this Journal, since, 

 apart from the late naturalist, Heron-Royer, no one has yet been 

 able to ascertain with anything approaching precision the number 

 of eggs that are laid by one female in the course of the breeding 

 season. 



There were two pairs of this species, the females both in 

 breeding condition ; but only one of the males appeared animated 

 with genesic ardour, showing himself most constant in his atten- 

 tions, not only to his legitimate mates, but even to a small Rana 

 temporaria sharing the same pond. 



Zool. Mh ser. vol. III., November, 1899. 2 l 



