19S 



HARDWICKE'S SCIENCE-GOS SIP. 



[Sept. 1, 1S66. 



fig. 189), the Lapidary Snail (E. lapicida, fig. 190), 

 the Rudely Snail {II. rufescens, fig. 191), the Rounded 

 Snail (H. rotinirhda, fig. 192), the Bellied Snail (H. 



Fig. 188. Zoned Snail (H. virguta). 



Fig. leg. Heath Snail (B". ericetorum). 



Fig. 190. Lapidary Snail {H. lapicida). 



nmlilicata), and the Pigmy Snail (E. pygmcea, fig. 

 193) ; together with three rare species, the Bulged 

 Snail (E. obvoluta), which occurs only in Hamp- 

 shire ; the Green Snail (E. revelata), found on the 



Fig. 191. Ruddy Snail (ff. rufescens). 



Fig. 192. Rounded Snail 

 (.H". rotundata). 



Fig. 193. Pigmy Snail 

 {H.pygmwa), enlarged. 



south coast : and the Membranous Snail (E. fused), 

 which is more widely distributed than the two 

 last-named species, being found sparingly in several 

 localities. On each of the species which we have 

 enumerated, a few remarks might with advantage 

 have been offered, but the space already occupied 

 must be our excuse for the omission, for which the 

 figures from nature will partly compensate. 



liM^sK®^ 



Fig. 194. Hybrid Snail {3. hybrid*). 



Lest any of our readers should be disposed to 

 regard II. hylrcUa as a distinct species, we have 

 furnished figures (fig. 191) of the shells. 



"W. Wallace Evfe. 



PWAI-NGYET. 



T HAVE noticed your remarks on the substance 

 -*- called Pwai-ngyet in your interesting little 

 periodical Science Gossip. As it was I who 

 furnished the bees which were forwarded by the 

 Agri-Horticultural Society of Calcutta to Mr. E. 

 Smith, of the British Museum, for identification, and 

 which he pronounced to be Trigona Iceviceps (as 

 Dr. Mason, to whom you refer, states in his book 

 on the natural productions of .the Tenasserim pro- 

 vinces) ; and as, therefore, I know both the sub- 

 stance and the insect well, I have great pleasure 

 in giving you such information as I can on the 

 subject. 



A few years ago, the secretary of the Calcutta 

 Agri-Horticultural Society wrote to me for informa- 

 tion regarding Pieai-ngyet. "Until then, I knew very 

 little about it ; but my attention having been called 

 in this way to it, I made it my business to find out 

 what it was. 



If I read. your remarks rightly, you appear to be 

 of opinion that Pwai-ngyet is the pure unaltered 

 gum or resin of Canari»„i strictum, only bored 

 and channelled by the bee. If this were so, then 

 the substance should only be found on that tree. 

 It is, however, found on different trees : sometimes 

 too in the ground, or in a hollow among rocks ; and, 

 occasionally, even in the hollow post of an old house. 



I have seen the bees making their nest in all these 

 several situations. 



Pwai-ngyet, I believe myself, is a combination of 

 various gums or resins, and probably also of oils, 

 gathered from various sources, while in a soft state, 

 by the bee, and built up and moulded, very much as 

 wax is moulded ; with this difference, that whereas 

 wax is formed by the honey-bee into cells of perfect 

 and uniform symmetry, the cells in Pwai-ngyet 

 assume no regular form at all. 



What trees contribute their juices to form Pwai- 

 ngyet I cannot say for certain, though I incline to 

 think that Thengan-tsee, or the resin of the Thengan 

 (Eopea odorata), is the chief ingredient, and that the 

 oil of the various Pipterocarps, or wood-oil trees, 

 particularly of Pipterocarpus lavis, the wood-oil 

 tree par excellence, also enters into the composition 

 of the material. My reasons for thinking so are, that 

 the texture, the colour, and the smell of Pioai-ngyet 

 are all such as would apparently result from a com- 

 bination of the two substances mentioned ; and, 

 that Hopea odorata and Pipterocarpus hevis are 

 among the principal giants of our forests, and 

 common trees. On the other hand, I do not think 

 (though I will not be sure) that Caiiariuui strictum 

 is found in our provinces, although I believe a 

 species of Canarium, a large timber tree, is fouud 

 in Pegu. 



The Tripona Imiceps builds its nest generally in 



