Page:The Zoologist, 4th series, vol 3 (1899).djvu/543

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THE ZOOLOGIST.

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 lævis 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 satisfaction, 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, Héron-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 attentions, not only to his legitimate mates, but even to a small Rana temporaria sharing the same pond.

Zool. 4th ser. vol. III., November, 1899.
2 l