This shell is either sinistral or dextral, cylindrically ovate, thick, stout and pupoid in the spire, bluish-white, tinged with a watery fawn-colour, and clouded throughout with oblique zigzag flames of the same colour, darker, but very undefined and washy; whorls seven, smooth, rather bulbous, faintly impressed concavely below the suture; aperture ovate, of rather moderate dimensions, overlaid in a very conspicuous manner across the body-whorl, and over a very thickly reflected lip, with a callous, opaque, milk-white deposit, which in the interior is stained with a beautifully iridescent violet-rose. This fine species, of which Mr. Stevens has received several specimens, measuring nearly 3 inches in length by 1-1/2 inch in width, is a most characteristic example of a type of the Malayan province of the genus, represented by the old _Bulimus citrinus_ of Brugnière; and it has been named after its well-authenticated place of habitation, because the species is, in all probability, confined to that locality. The islands adjacent to Cambodia have been pretty well ransacked; and we have nothing like it in species either from them or from the contiguous mainland of Siam on the west, or Cochin China on the east. This particular type of the genus appears, however, abundantly at the Moluccas, in _B. citrinus_; and at Mindanao, the southernmost of the Philippine Islands, in _B. maculiferus_. Like these two species, _B. cambojiensis_ occurs with the shell convoluted either to the right or to the left. The shell is both larger and stouter than that of _B. citrinus_, differently painted, and especially characterized by its mouth of iridescent violet-rose, or what is now fashionably termed “Solferino” colour. These descriptions are from the pen of Lovell Reeve, Esq., F.L.S., &c., and were communicated by him to ‘The Annals and Magazine of Natural History.’ See vol. vi. p. 203. The annexed plate contains representations of several other new and interesting species of land shells discovered by M. Mouhot, and named by Dr. Pfeiffer, but which have yet to be described. [Illustration: New Land Shells discovered by M. Mouhot. G. B. Sowerby lith. W. West imp. _1. 2. Alycæus Mouhoti, Pf^r._ _3. Helix deliciosa, Pf^r._ _4. Bulisnus Römeri, Pf^r._ _5. Clausilia Mouhoti, Pf^r._ _6. Streplaxis pellucens, Pf^r._ _7. Pupina Mouhoti, Pf^r._ _8. Helix illustris, Pf^r._ _9. 10. Helix Laomontana, Pf^r._ _11. 12. Helix beligna, Pf^r._ _13. Hybocistis Mouhoti, Pf^r._ _14. Trochatella Mouhoti, Pf^r._ _15. Helix horrida, Pf^r._] ATMOSPHERICAL OBSERVATIONS. ATMOSPHERICAL OBSERVATIONS.