152 THE ZOOLOGIST. 



books, no mention of a whistle is made in the description of the note of 

 either the Little Crake or Baillon's Crake. It has been suggested to me 

 that the bird in question was one of the Phalaropes, but I believe the note 

 of this species is very different to that above described. — E. A. Swatnson 

 (Woodlands, Brecon). 



[We should think the bird in question was more likely to have been a 

 Spotted Crake, which looks very small when swimming, owing to the legs 

 being invisible, half the body submerged, and the feathers of the dorsal 

 plumage compactly compressed ; but the description given is too vague to 

 warrant any decided opinion as to the species. — Ed.] 



REPTILES. 



Variations of the Viper.— Having at various times kept Vipers- 

 altogether about a dozen — in captivity, I was much interested in Mr. 

 Boulenger's paper (pp. 87 — 93) on the variations of that species, and 

 T venture to suggest that, in treating of variation in colour, he has not 

 sufficiently taken into account the effect of sloughing. He does not state 

 whether he kept any of his specimens alive, or whether he knew of any of 

 them having recently cast their skius. I have seen a very dusky male 

 Viper (Pelias berus) become by this process one of the lightest, its ground- 

 colour being changed to a light stone-grey ; and T have also seen a Common 

 Snake (Tropidonotus natrix), which was of a mahogany or dull red hue, 

 change in a similar way to a lovely and lustrous green, with every black 

 mark as distinct as though mapped in with printers' ink. Judging by 

 some twenty years' observation of British Vipers, Snakes, and Lizards, both 

 in their wild state and in large cages, I conclude that in all these reptiles, 

 and also in the Slow-worm (Anguis fragilis), the size of head is of value 

 as indicating age. I am certain that when first the young attain a fair 

 average size, their heads, in comparison with their bodies, are proportionately 

 much smaller than those of more mature individuals ; and the firmness and 

 weight of the cranial bones of some of the latter lead me to believe that 

 these may have attained to a very considerable age. A Slow-worm I had, 

 eleven years old, and eighteen inches long, was not nearly so marked 

 in this particular, nor so robust, as several tailless specimens of the 

 same species which T have seen. I have caught many more Vipers than 

 T have kept ; in fact, whenever T see a Viper I try to catch it, — with a fair 

 chance of success, — and after holding it a little, in order to make it less 

 careless and liable to be destroyed, I let it go. The largest I have ever 

 seen was locally a giant; I kept it for two months, and again and again 

 placed it in a long box, where I could measure it as accurately as a living 

 snake ever can be measured, and it was considerably over 26 in., but not 

 more than 26£ in. in lengh: 2G| in. was about the exact extent of this 

 Bpecimen, which was a female. The head was very large, and when caught 



