There is the widest difference, both among poisonous and non-poisonous snakes, not alone in nervousness and irascibility but also in ability to accustom themselves to out-of-the-way surroundings.  Many species of non-poisonous snakes which are entirely harmless, to man or to any other animal except their small prey, are nevertheless very vicious and truculent, striking right and left and biting freely on the smallest provocation—­this is the case with the species of which the doctor had previously placed a specimen on the table.  Moreover, many snakes, some entirely harmless and some vicious ones, are so nervous and uneasy that it is with the greatest difficulty they can be induced to eat in captivity, and the slightest disturbance or interference will prevent their eating.  There are other snakes, however, of which the mussurama is perhaps the best example, which are very good captives, and at the same time very fearless, showing a complete indifference not only to being observed but to being handled when they are feeding.

There is in the United States a beautiful and attractive snake, the king-snake, with much the same habits as the mussurama.  It is friendly toward mankind, and not poisonous, so that it can be handled freely.  It feeds on other serpents, and will kill a rattlesnake as big as itself, being immune to the rattlesnake venom.  Mr. Ditmars, of the Bronx Zoo, has made many interesting experiments with these king-snakes.  I have had them in my own possession.  They are good-natured and can generally be handled with impunity, but I have known them to bite, whereas Doctor Brazil informed me that it was almost impossible to make the mussurama bite a man.  The king-snake will feed greedily on other snakes in the presence of man—­I knew of one case where it partly swallowed another snake while both were in a small boy’s pocket.  It is immune to viper poison but it is not immune to colubrine poison.  A couple of years ago I was informed of a case where one of these king-snakes was put into an enclosure with an Indian snake-eating cobra or hamadryad of about the same size.  It killed the cobra but made no effort to swallow it, and very soon showed the effects of the cobra poison.  I believe it afterward died, but unfortunately I have mislaid my notes and cannot now remember the details of the incident.

Doctor Brazil informed me that the mussurama, like the king-snake, was not immune to the colubrine poison.  A mussurama in his possession, which had with impunity killed and eaten several rattlesnakes and representatives of the lachecis genus, also killed and ate a venomous coral-snake, but shortly afterward itself died from the effects of the poison.  It is one of the many puzzles of nature that these American serpents which kill poisonous serpents should only have grown immune to the poison of the most dangerous American poisonous serpents, the pit-vipers, and should not have become immune to the poison of the coral-snakes which are