This is the snake to which almost this book owes its origin, the specimens at the Zoological Gardens called ‘Moccasins’ tripping me up at the outset, as my preface sets forth. Holbrooke describes it as spending most of its time in the water, or about pond and river banks. It swims rapidly, and hundreds may be seen darting in all directions through the water. They are very common in the United States, and might have formed the ‘wreathed myriads’ on Lake Erie formerly. In summer they roost on the lower branches of trees, overhanging the water, like Trigonocephalus piscivorus, the true ‘water moccasin,’ or ‘cotton mouth.’ At the time of writing there are examples of both these at the Gardens, the harmless ‘moccasin,’ a rather handsome snake, and the venomous one (not there recognised as the well-known moccasin of the United States), so nearly black that we can account for its being occasionally called the ‘black water viper.’
It is probably Tropidonotus which Parker Gilmore describes as ‘water vipers.’[73] At Vincennes in Indiana, he says, ‘On the side where some alder bushes grow in the water, I have seen, on a very warm and bright day, such numbers of water vipers twined round the limbs and trunks which margin the pond, that it would be almost impossible to wade a yard without being within reach of one of them. They certainly have all the appearance of being venomous; the inhabitants say, however, they are harmless. They feed principally on fish, frogs, and small birds.’
Of American water snakes, the anaconda deserves special mention. Of it Seba says, ‘Ce serpent habite plus les eaux que les rochers;’ and in its having the nostrils situated on the top of the head, and in possessing some other features in common with the Homalopsidæ, we are justified in calling it a water serpent, notwithstanding it is a true constrictor. ‘Mother of waters,’ the aborigines of South America call it. It is the Boa aquatica of Neuwied, and Eunectes murinus of Wagler, the latter name being the one most frequently used by modern herpetologists. Dumeril adopts it, l’Eunect murin, giving the origin of the generic name, bon nageur, from the Greek εὐ, bien, fort, and νηϰτής, nageur—qui nage bien. As to the meaning of the specific name murinus, there can be but little doubt, though some have attributed it to its mouse-coloured skin or spots. Le mangeur de rats, Bonnat called it; le rativoro, Lacepède. Seba, who was one of the first to describe it, says, ‘Il font guerre aux rats;’ and Bonnat, on his authority, says, ‘Il se nourrit d’une espèce de rats.’ ‘Serpent d’Amerique à moucheteur de tortue,’ Seba also describes it, and with ‘jolies écailles magnifiquement madrées de grandes taches, semblable de celles des tortues; taches semées sans ordres, grands, petits,’ etc. Murinus, therefore, clearly refers to its food, not its colour.
Dumeril’s description is of more scientific exactness: ‘Pas de fossettes aux lèvres. On peut aisément reconnaitre les Eunectes seul entre les boa, ils ont les narines percées à la face supérieure du bout du museau et directement tournées vers le ciel.’ These, being extremely small, and with a power to close hermetically, declare its aquatic habits. Its eyes are prominent, and so placed that the reptile can see before it, and also below—that is, down into the waters.
On first sight it might be a matter of wonder that so large a serpent should condescend to a meal of rats and mice; but to explain this we must again go back to the early naturalists, when we discover that what Seba called le rat d’Amerique was a rodent quite worth constricting for dinner. Under the order Muridæ were included in those days a number of the larger rodents, such as the Paca, Mus Braziliensis; the Coypu, Mus coypus; Myopotamus, the Capybara; the Murine opossum, and several others, aquatic in their habits, and large enough to attract the ‘Giant of the Waters.’
From the vernacular Matatoro, or ‘Bull killer,’ also a whole century of misrepresentations have arisen, the said ‘bull’ being really as small in proportion as the ‘rats’ and ‘mice’ were large. ‘The deer swallower’ is another of its local titles, showing that it is a serpent of varying tastes. Stories are told of this ‘monster’ killing itself in attempting to gorge large animals with enormously extended horns, animals not to be found among the Brazilian fauna; and familiar to most persons are the illustrations of anacondas of untraceable length, the posterior portion coiled round a branch fifty feet high, and the anterior coiled round a bull as big as a prize ox. These illustrations are the offspring of ignorance rather than reality, and though occasionally Eunectes might come to grief by attacking a somewhat unmanageable meal, yet its recognised specific, murinus or murina, points more clearly the true nature of its food, viz. rodents of at most some two feet long.
No less exaggerated than its appetite is its length. Possibly anacondas may have attained greater size formerly when there were fewer enemies than at present, if it be true, as some have affirmed, that serpents grow all their lives. Thirty feet is the utmost length on record. Wallace affirms that he has never seen one exceeding twenty feet. Those individuals at the Zoological Gardens have rarely exceeded this, and Günther gives twenty-two feet as their average length in the present day.
Of those known in South Africa as ‘water snakes,’ one is Avusamans vernacularly, a black one and common, and another, Iffulu, of a beautiful bright green. Mr. Woodward, whose scientific egg-sucker has been already mentioned in chap. iii., states that both these are poisonous, that he never saw the green one out of water, and that it is unsafe to bathe where they are. On referring to Dr. Andrew Smith’s Zoology of South Africa, I am not able to identify these with certainty, and do not, therefore, give the above as scientific information.