198 THE ZOOLOGIST. 



opening the incubator a couple of weeks after the insertion of some well* 

 developed eggs " curious squeaking sounds were heard coming from the 

 inside of the eggs, the sounds which in nature tell the mother that her 

 young are about ready to hatch, and should be helped out of the mass of 

 earth and leaves in which they are buried. These sounds are audible at a 

 distance of fifteen yards or more, so that even when the eggs are buried in 

 the nest the parent is probably able to hear the call of her young. The 

 next day after the first sound was heard, one of the Alligators broke out of 

 its shell, and a couple of days later two more hatched. 



We have received a Report on the Sarawak Museum, written by Mr. R. 

 Shelford, the Curator, dated February, 1901. Apart from the details of 

 the very satisfactory progress in the growth of this happily situated institu- 

 tion, the most interesting biological information relates to the seasonal 

 variation in the Rhopalocera. Mr. Shelford writes : — 



" It is noteworthy that Borneau butterflies do not, to any great extent, 

 exhibit seasonal variation ; such species that do are quite irregular in their 

 appearance, e. g. the collection contains a long series of the so-called wet- and 

 dry-season forms of Melanitis ismene (Cr.) which have been caught at all 

 mouths of the year, and many examples of both forms have been caught in 

 the same mouth. Neopithecops gaura (Butl.) is equally erratic in variability. 

 It appears probable that the markings and colouration of the images of 

 these variable forms are dependent on the degree of damp or dryness to 

 which the young stages (egg, larva, or pupa) are subjected ; if this is indeed 

 the case, a spell of wet weather iri the fine monsoon — a by no means unusual 

 event — would produce a crop of wet-season forms, and conversely a spell of 

 fine weather in the wet monsoon a crop of dry -season forms." 



Mr. Lionel de Niceville, who has recently been appointed "Ento- 

 mologist " to the Indian Museum, Calcutta, has recently published a most 

 valuable paper on " The Food-Plants of the Butterflies of the Kanara 

 District of the Bombay Presidency" (Journ. Asiat. Soc. Bengal, vol. Ixix. 

 pp. 187-278). Apart from food-plants, the larvae of many butterflies will, 

 when they cannot obtain vegetable food, eat each other, or soft newly-formed 

 pupae. The LyccEnida, appear to have the distinction in cannibalistic pro- 

 pensities. One larva of Tajura cippus has been known to eat up over a 

 dozen young ones of its own species. The tendency to cannibalism is not 

 confined to the Lycanidce, but exists also among the Pierintn ; the larvae of 

 Appias will eat each other, and any other species of larvae feeding on the 

 same food-plant as themselves, if forced to it by hunger. 



