THE CYANIDE REACTION WITH YELLOW LEPlDOfTERA. lOo 



GALLERIID^. 



Galleria mellonella, L., Harefield, very frequent, sometimes 

 injurious, causing destruction of weak hives {Wall). 



Aphomia sociclla, L., Harefield, once taken (Wall) ; Wliitton 

 (Bendall) ; [Northwood (South)] . 



Achrcea grisella, Fb., Harefield, common {Wall). 



(To be continued.) 

 Institute of Jaioiaica, Kingston, Jamaica, Aug. 21, 1892. 



THE CYANIDE-EEACTION WITH YELLOW LEPIDOPTEEA. 

 By F. H. Perry Coste, B.Sc. (Lend.), F.C.S., F.L.S. 

 (Concluded from p. 85.) 

 V. — Efpect of Lithium Salts. 



Having so disposed of the alkalis, it seemed highly desirable 

 to ascertain what effect salts of the alkaline earths would have. 

 A number of salts of calcium, barium, and strontium were there- 

 fore tested; and, in addition to these, salts of zinc and uiagnesium, 

 of several lieavy metals, and also several organic acids, were 

 tested ; the test being in each instance made by exposing to their 

 action wings of species that were known to be susceptible. The 

 vast majority of these results were negative, no reaction, such as 

 was sought for, being obtained. 



In a few cases, howevei', positive results were obtained. 

 Barium chloride, zincic sulphate, and also — strangely enough — 

 salicylic and succinic acids, were found to give the purple-pink 

 reaction more or less faintly. The reaction with zinc sulphate is 

 interesting, in that the under side of the wing itself was observed 

 to have become almost a "cyanide-red." This seems to offer 

 some hope of connecting together the cyanide and the lithium 

 reactions. Again, in the experiments with salicylic acid and 

 with barium chloride it was observed that there was a faint pink 

 tinge on the wing itself, as well as on the surface of the acid ; 

 whereas, in the majority of the experiments, this pink was 

 found only on the surface of the chemical used. 



The most promising of these last experiments had been that 

 made with barium chloride, and it was, therefore, thought worth 

 while to make a set of experiments with this reagent. Barium 

 chloride was, therefore, tested by exposing to it a large number of 

 species, just as in the case of lithium sulphate ; and the results are 

 confirmatory of the lithium results. Here, again, the reaction was 

 obtained from several of the Pieridse, e. g., C. edusa and C. hyale, 



