January 1, 1898.] 



KNOWLEDGE. 



SERPENTS AND HOW TO RECOGNIZE THEM. 



By Lionel Jervis. 



THE casual visitor to the Zoological Gardens should 

 have little difficulty aa a rule in identifying a 

 snake. The name is written underneath in Greek 

 or Latin, or half in Greek and half in Latin, or in 

 a latinization of local names, as, for instance, in 

 the case of the hamadryad, Xaja huniidnis : Najn being, 

 I take it, an adaptation of " nag," which is the Hindi 

 for cobra, and Ihoiiikihs, I suppose, originates iu the 

 bun<i<iriiiii of Russell's " Indian Serpents." 



For all that, the scientific names are better than the 

 local cues. Take, for example, the Lucliesis lanceuhitus. 

 Perhaps Bothi-o/>s or Ti-iijonocfphatus are more familiar 

 titles than the comparatively recent Lachesis, but every- 

 one knows what the La-lnsin, Uothrops, or Triiionocejihaltis 

 liniceolatus is ; it is, of course, the fer-ile-lance. Com- 

 bining the nearly related Lachesiti atrox (the difference 

 between the species is so slight that even specialists are 

 unable to differentiate offhand), let us see how many local 

 names we can find. First there is the fer-di'-lance, then 

 follow the rat-tailed pit-viper, the lance-headed viper, 

 the deadly snake ("deadly" is a "very vile" prefix, 

 quite unworthy of the Zoological Society, who, if I am 

 not mistaken, were guilty of it), the jararaca, the yellow 

 viper, the whip snake, the Labarri snake, and I dare say 

 that there are half a doizen other names in Tropical 

 America for this serpent. Nevertheless it is, I think, 

 better to leave the local English name alone than to invent 

 one. Look at the shielded death adder {Xotechis scut'ttm), 

 till recently known as the short-death adder {tlo/din,-- 

 lihnlun cHitits). The colonists call it, very happily, the 

 tiger or brown-banded snake — a look at the serpent will 

 show you why. But here we have " death adder. ' Why 

 " death adder " '? The death adder of the colonists, the 

 "unqualified" death adder of Regent's Park — the Ac<iii- 

 thopis antaicticiis — is about as unlike a tiger snake as 

 it well can be. The tiger snake has a cylindrical body, 

 tapering into a respectably proportionate tail ; the body 

 of the death adder is bloated, and terminates in a short 

 compressed tail with a spike at the end of it. In both the 

 head is distinct from the neck : that of the tiger snake, 

 which resembles a cobra's, very slightly ; that of the death 

 adder, which resembles a viper's, very markedly. The 

 prefix " shielded " is good enough, but " short" is not so 

 happy, considering that the Xotcclns is about twice the 

 length of the AcantJwpis. Again, why " purplish death 

 adder" instead of "black snake"? Why not confine 

 " death adder " to the Acanthopis instead of applying it 

 aimlessly to almost every poisonous snake in Australia ? 



•Just one more warning as to the danger of trusting to 

 the accuracy or sense of either the English or scientific 

 title. Everyone has heard of the beautiful and venomous 

 coral snake of Tropical America. It is very brilliantly 

 marked with rings of black and red, with thin whitish 

 edges to the black rings, and from this the Spanish- 

 speaking inhabitants very happily named it the "corral"' 

 or " ringed " snake. Some naturalistic genius gets hold 

 of this, and, forcing the local name into Latin, calls it 

 Elaps o'l-allinKs, thereby misleading people into the idea 

 that it is a bright red snake, and called conillinus from its 

 resemblance to coral. 



Nevertheless the descriptive label furnishes the accepted 

 name, such as it is ; but labels are very little use when 

 there are two or three different species in one case, as 

 snakes cannot be expected to remain opposite their 

 respective descriptions, any more than monkeys. How, 



then, are we to identify them V Coloration is not always a 

 sure guide. Look once again at the TmcIiisis lanceolatus. 

 It may be of one uniform colour above — grey, brown, 

 yellow, reddish, or olive, or it may be any of these colours 

 with regular or irregular dark markings, or almost any 

 combination of the foregoing. 



In a short article, or even in a small pamphlet, it would 

 be impossible to give a " ready recognizer," even for 

 snakes which are easily distinguished by specialists. I 

 shall therefore content myself with giving an object lesson 

 from the small genus Ancistrodoii,'- of the sub-family 

 Crotalinm, or pit-vipers. 



The first distinguishing feature is the pit in the loreal 

 region, between the eyes and the nose. This pit charac- 

 terises a group of poisonous snakes the bite of which is 

 sure to entail very unpleasant, often fatal, consequences. 

 This group falls into two main divisions — those which have 

 rattles on their tails and those which have not. Of course 

 a snake with a rattle on its tail is a rattlesnake, and when 

 you see a serpent of this kind you are quite safe in saying : 

 "That is a poisonous American serpent"; and if it is 

 described as ' lotalus tenijini.s, you may, if you like to take 

 a slight risk, add: " That is the only one of the kind found 

 south of Mexico." But there is a pitfall here, as you are 

 quite likely to find the South American rattler described 

 as " mohixsu.s" or " huniiluK," and " trn-iiicn.\" has been 

 applied to the water-rattle. Oh for an universal classifi- 

 cation ! 



The pit-vipers which have no rattle, again, fall into two 

 subdivisions : those in which the head is covered with scales, 

 the Ldchfsis, and those in which the head is shielded by 

 nine symmetrical plates, the Ancistrodon. So, then, if you 

 find a serpent with a pit between the eyes and the nose 

 (not with two or more pits in the upper lip shields), with 

 the head covered with nine shield-like plates, and with no 

 rattle on its tail, you have an Ancistrodon. 



Of course the most satisfactory state in which to examine 

 a poisonous snake is when it is dead and pickled. If alive, 

 the best thing to do is to secure its neck in a snake-loop. 

 Fail'ing this, you must content yourself with looking at it 

 through glass or wire or from a safe distance. The first 

 part of the following descriptions will, therefore, apply when 

 the snake can be examined minutely ; the second when it 

 can be seen only under comparative difficulties. In some 

 cases the colour pattern, together with the data already given 

 as to the pit, etc., will be sufficient to identify the serpent. 



First I select the only species of the subdivision in 

 which the second upper labial forms part of the border of 

 the loreal pit and the sub-caudal shields are in pairs. 



.4. hijpnale.f — By these features you cannot fail to 

 recognize the snake on close examination ; otherwise it is 

 not so easy to identify. It is only a little bit of a snake, 

 with a turned-up nose. The colour is generally dark — 

 usually greyish or brown — with or without spots, and the 

 markings on the head are ill-defined. The internasals and 

 praefrontals, it is true, are broken up into scales, but you 

 usually require a magnifying glass to make this out. The 

 local name on the west coast of India and in Ceylon, 

 where it is found, is the "carawila. " As far as I know, 

 there is but little danger attending the bite. 



A. piscirdrw.] — The first of four species in which the 

 second upper labial forms part of the border of the pit, 

 and some of the sub-caudals are single, some in pairs. 



Remarkable for being the only one of the Ancktrodonin 

 which the loreal is absent. The sub-caudals are sometimes 



* Greek : ■• fish-hook toothed." f Oreek : " seudiag to sleep." 

 i Latin ; •' fish-eating." 



