1895.] H. H. Godwin- Austen — Notes on Indian Land Mollusca. 151 



6. The bleaching of colours takes place less rapidly when the 

 colours are in solution than when they are dyed on fabrics. 



7. The bleaching of colours in solution takes place less rapidly if 

 the living germs or organisms in the solutions are destroyed by boiling 

 than if they be not so destroyed. 



8. The bleaching action of light appears to be more powerful if 

 the colours are in contact with an organic fabric than if they are used 

 to colour inorganic materials (asbestus). 



9. The bleaching action of light in presence of air is much facili- 

 tated by the presence of moisture in contact with the colours and more 

 particularly of evaporating water in contact with dyed fabrics. 



10. There can therefore be little doubt that the bleaching action 

 of light on ordinary organic colouring matters is usually due to oxidation. 

 This oxidation when facilitated by evaporating water is probably or almost 

 certainly due to the action of ozone, for Gorup von Besanez has shown 

 that ozone is invariably foi'med when water evaporates in the air.* It 

 therefore appears highly probable also that the action of the sunlight 

 on the oxygen of the air brings it into an active condition (resembling 

 perhaps that of ozone), and that the bleaching of organic colours is due 

 to oxidation from this cause ; for ordinary oxygen uninfluenced by 

 sunlight does not bleach. 



No. 3. Notes on, and drawings of, the animals of various Indian Land 

 Mollusca (Pulmonifera). — By Lieut.-Colonel H. H, Godwin-Austen, 

 F.R.S., F.Z.S., &c. 



[Read 3rd April.] 



Plate VII. 

 Continued from J. A. 8. B., Pt. ii., Vol. LI, 1882,^. 71. 



After the long lapse of 12 years since publishing my second paper 

 (in 1882), on the drawings of Indian Land-Mollusca made by native 

 artists under the superintendence of Ferdinand Stoliczka, I now 

 forward a third, with the hope that it will lead some of our younger 

 naturalists to make notes and drawings, and if possible dissections, of 

 Indian species, so that they may be more accurately placed in generic 

 position. 



The first I have to notice and reproduce on Plate vii, fig. 1, is No. 29 

 of Ferd. Stoliczka's drawings, a very careful and accurate one of Helix 

 octhoplax, with his MS. note attached, — " Asalu ; sent down by Major 

 God win- Austen." In 1869 I was surveying in the Naga Hills and 



* Ann. Chem. Pharm. clxi. 232; also Roscoe and Schorl emmer Treatise on 

 Chemistry Vol. I., p. 200. 



