3152 British Entomological Society. 



of the smallest (the violet) undulations of light. Upon turning the plate, and arran- 

 ging it in a rather different manner, coloured representations of the whole of the twelve 

 systems are produced, not, as in the former instance, in the air, but in the glass ; and 

 upon comparing these with the aerial spectrum, it is found that the colour of the sys- 

 tem F, being deep red, agrees with that of A in the aerial spectrum, G with B, and in 

 like manner the following systems, H, I, K, L, M, with those of the former, C, D, E, 

 F, G ; and by uniting the numerical values for the distances of the lines harmonizing 

 in their colours, the main result is that the length of the undulations in the glass is in 

 proportion to that of those in the air, as 1 to 1.53, furnishing a direct confirmation of 

 the undulatory theory. The correctness of these results was also stated to depend on 

 the absolute accuracy of the distances of the lines, as an error of only goouoo °f a Paris 

 line was found to produce stripes of other colours, and if the distance of the lines in 

 system M (that which produces the violet rays in the glass spectrum) is diminished by 

 only z \ of that amount, the colour will entirely disappear. — J. W. 



Proceedings of the British Entomological Society. 



The May meeting of this Society was held at the Society's rooms, 10, Fountain- 

 place, City-road, on the 5th instant ; Mr. Harding, President, in the chair. 



The following insects were exhibited, all of them captured during the present year. 



Notodonta carmelita, a fine specimen, taken at Shirley, Surrey. 



Celaena agathina, taken at Darenth, on sallow blossoms. This is a new locality 

 for this insect. 



Spilonota pauperana, several specimens. 



Grapholitha Paykulliana. 



Eupaecilia abbreviata, on sallow blossoms. 



Semioscopis Avellanella. 



Taeniocampa gracilis, and many others. 



Mr. Norman read the following account of the habits of a species of spider, from 

 Dickens's ' Household Words ' of April 5. 



" It was to record an instance of insect talent and ingenuity, which it was my good 

 fortune to observe in the gorgeous forests of British Guiana, that I took up my pen ; 

 before doing so, however, let me offer a few brief remarks on other members of the 

 same family, which are natives of Guiana. In applying the term ' insects' to spiders, 

 I adopt the classification of the older entomologists ; for the moderns have, with a 

 considerable show of reason, placed them beyond the pale of the true Insecta. We 

 ever find the various forms of animal life most numerous, where their peculiar food is 

 in the greatest abundance; and it is to this cause we must assign the comparatively 

 small number of spiders which inhabit South America; for the Diptera, or two-winged 

 flies, which furnish their principal supply of food, are in no country so limited in num- 

 ber : and this is the more surprising, as nowhere are the other classes of insects so 

 plentiful. It is probable, however, that but a very small portion of the spider family 

 have as yet been discovered, from the fact that great numbers infest the topmost 

 branches of the trees in the forests of the interior, where they escape the eye of the 

 few collectors who have penetrated to their haunts, and are only thought to be found 

 on inspection of the crops of various insect-feeding birds. This supposition becomes 

 greatly confirmed, when we remember the many previously unknown species which 





