On two occasions at the Gardens within the time specified, hybrids have been born between Epicratis angulifer and Chilobothrus inornatus, and I can but think that occurrences of this nature must happen among snakes in their wild state occasionally, which may throw some light on the perplexities of classifiers.
In August 1878, three were born alive; and in recording the event the Secretary to the Zoological Society, P. Lutley Sclater, Esq., Ph.D., F.R.S., etc., writes that there can be no question as to the pairing of these two snakes, both in the same cage, and as there was no male Epicratis in the collection. Three were alive and six bad eggs were produced.
In September 1879, two more hybrids were born between the same pair; who, at any rate, remained constant to each other.
Of the venomous serpents that have fallen under my own notice at the Zoological Gardens, the little Indian viper (Echis carinata) had three young ones in July 1875. Only two survived a few weeks. They changed their coat at an early day, but ate nothing; nor did the mother, who soon died. One may mention here that the vipers in collections rarely do survive long after giving birth to young. This may be only owing to an unhealthy condition in captivity, but merits inquiry.
Four common adders (Vipera berus) and several broods of the Daboia have also been produced.
The African viper of the coloured illustration is another example, as having afforded opportunities for observation.
In point of numbers we find the families varying from three or four to upwards of a hundred. When the parent is in health, the young are produced easily and rapidly. Vipera nasicornis deposited her forty-six children within about three hours. A Java snake (though not in our London Ophidarium) produced twenty-four young ones in twenty minutes. Anaconda, in April 1877, on the contrary, exhibited considerable protraction, extruding bad eggs at irregular intervals for many days. She will form the subject of the next chapter.
Incubation, or the hatching of eggs by the maternal warmth, seems not to have been suspected by ophiologists until a comparatively recent date; but by the non-scientific, the barbarian and the untutored natives of hot countries, who see, but dream not that in future ages what they saw and incidentally spoke of would be of weight to the enlightened of as yet unexisting nations,—by such the fact was known long ere its worth as a fact was recognised. Yet, as has been already seen in these pages, evidence given without intent and purpose often is of scientific importance. Aristotle spoke of incubation; but with classic writers the difficulty of sifting fact from fable may cause the whole to be rejected.
We owe to Zoological Societies and menageries the confirmation of the couvaison of at least one species of serpents. Subsequently we are told, ‘The python only incubates,’ this snake being generally mentioned as the one exception; and only within a very few years has maternal affection been accredited to any others. Mr. P. H. Gosse was informed by the negroes in Jamaica of the habits of the yellow boa. Sir Joseph Fayrer was informed by the jugglers that ‘over and over again they had dug cobras out of their holes sitting on their eggs.’ Dr. E. Nicholson was informed ‘on trustworthy authority that the Hamadryad has been found coiled upon a nest of evidently artificial construction.’ He thinks snakes always watch over their eggs, and frequent the locality where they have deposited them. The keeper at the Gardens confirms this by his own observations. ‘They do care for their eggs in their own way,’ he assured me, and display unusual irritability and wildness at such times.[130] In menageries, however, their habits are always more or less artificial; they cannot seek spots for themselves, or exercise maternal instinct beyond doing the best they can under the circumstances. Anything in the way of extra indulgences, such as soft rubbish, moss, or sand, is duly appreciated when eggs are about to be deposited, and we find maternal ophidians resort at once to this.