18G1.] DR. A. GiJNTHER ON BRAZILIAN REPTILES. 13 



condition that they died very shortly afterwards. It became e\-ident, 

 from the emaciated state of the latter, that those animals had been 

 killed, not by the change of the temperature, but by want of food and 

 water. Those tropical animals naturally require a greater supply of 

 the latter than our European species do ; and perhaps it would be 

 better to place them during the transport in a cool place on board 

 the steamer, in order to subdue the natural functions and to lessen 

 the desire for food. Once every week, on a bright day, they ought 

 to be brought on deck and exposed to the sun ; then some water 

 might be poured into the cage or box in which they are kept. I 

 have no doubt that the failures hitherto experienced in bringing over 

 the beautiful Hylce of the Tropics, and other reptiles living in damp 

 places, might be avoided by the adoption of the measures recom- 

 mended. 



As it is, however, only three of Dr. Wucherer's specimens sur- 

 vive — a beautiful specimen of the South American Rat-Snake, Spi- 

 lotes variabilis, about 6 feet long, one Polychrus marmoratus, and 

 one Philodryas viiidisshnus. The two former are exhibited for the 

 first time, and apparently are doing very well. The Rat-Snake feeds 

 regularly on birds and small mammals ; Dr. Wucherer has observed 

 that this species has the power of setting its tail in a trembling motion, 

 like the Rattle-Snake, if made angry. I have once seen the same in 

 the specimen living in the Gardens, and several times in the North 

 American Coluber quadrivittatus, whenever it was attacked by a 

 dog : in the latter case, it was not fear which produced the trembling 

 motion of the tail ; for it was immediately followed by the snake 

 striking at the dog*. 



The specimens of Polychrus marmoratus show the remarkable pe- 

 culiarity, that their femoral pores are not visible ; this has been ob- 

 served also by Bibrou, who says that they are often very indistinct 

 in this species. It changes its colours, like the Chamajleon, the 

 name of which has been conferred on it by the inhabitants of Bahia. 

 Its ground-colour is brown when it is cold or asleep, bright green 

 when it feels comfortable, and yellowish-green when exposed to great 

 heat. Also the great capacitj' of the lungs and the lively motion of 

 the eyes (which, however, act in concert with each other) remind one 

 of its representative of the Old World. Since it has been removed 

 to a warmer place than the cages in the Reptile-house are, it has re- 

 covered its full strength, feeds regularly on meal-worms, and is very 

 fond of milk. Being a Tree-Lizard, its favourite place is on the 

 branches of a large geranium, near the fire-place ; but even that place 

 is sometimes too cold for it ; and then it will approach nearer to 

 the fire than it is possible to keep the hand for any length of time. 

 Nevertheless it lies there basking for hours, extending the neck towards 

 the fire, and stretching the hind limbs in a line with the tail. These 

 animals will drink much ; and the quantity of water swallowed on a 

 single day by this specimen, the body of which does not exceed the 

 length of 5 inches, cannot be less than half an ounce. 



* The young of Cenchris piscivorus, born alive in the Gardens about the middle 

 of February, show this peculiar motion more frequently than any other of the 

 species mentioned. — March 5. 



