1904.] 89 



" Eoyal TJotanic Garrlens, Ppradeniya : 

 " Jan. \2th. 



"Dkar Sir, — Tlie flies liavo not lieon killed by the jcssamiiio leaves; but have 

 succumbed to a disease caused by a parasite fungus. The bodies of the dead flies 

 are full of the mycelium and spores of the fungus. These flics had probably been 

 feasting together upon some infected material, had simultaneously caught the 

 disease, and had gone ofp to die together upon the leaves of the first convenient 

 plant. This habit of congregating before death is not unusual vy^ith flies. A similar 

 case came to my notice two years ago, when a correspondent sent me a leaf of a 

 ' Malaboda ' {Mt/rintica latirifolia) upon which were some thirty dead ' bluebottle ' 

 flies. He wrote me that this leaf was one from a small bush growing by the side of 

 a jungle path, and that each leaf was similarly ornamented with dead flies, so much 

 so, that the bush looked quite blue. An occurrence of the same kind is recorded 

 in the American publication ' Insect Life ' (Vol. iv, p. 153), in which the following 

 paragraph appears : — 



"' The comparative scarcity of flies of all sorts this summer in the district has 

 been a matter of comment, whereas in neighbouring towns flies have been unusually 

 troublesome. This anomaly may find its explanation in the remarkable destruction 

 of certain flies by a common Empusa disease. In a recent stroll through the 

 grounds of the Agricultural Department, the under-side of the leaves of various 

 trees were found to be quite thickly covered with dead flies, attached by a fungous 

 growth. The abundance of the flies can be surmised from the fact that a single leaf 

 not infrequently contained as many as eight or ten specimens. The flies, for the 

 most part, belong to a common species, Pollenia rtidis, which occurs abundantly in 

 the late summer on outdoor vegetation, but include various smaller forms, some of 

 which are probably referable to the house-fly. The disease is not the common 

 fungous disease of the house-fly {Empusa muscee), isolated cases of which are not 

 uncommon in houses, but af E. americana, which occurs as far as known always out- 

 doors on vegetation, &c.' 



" It would be interesting to learn whether your correspondent has observed any 

 local diminution in the number of house flies as a result of the prevalence of this 

 disease 



" The Government Mycologist has examined the fungus, and reports that it is 

 undoubtedly a species of Empusa, and either identical with or closely allied to 

 E. musccB. — Tours sincerely, 



" ERNEST E. GREEN, 



" Government Entomologist." 

 Ceylon Observer: Jan. 13th, 1904. 



Botj/s nubilalis Hb., in Suffolk. -My friend Mr. A. E. Gibbs bas allowed me 

 the opportunily of examining a Pyralis which fell to his net last summer while at 

 Felixtowe, but which he was not acquainted with. It proves to be the extremely 

 rare Botys nubilalis, Hb., = silacealis, Hb., lupidinalis, L., and as it occurred, as 

 usual, singly, furnished no clue to the habits of the species. It is not of the 

 brownish-olive form, but pale yellow, = the silacealis variety. — Chas. G. Baebktt, 

 Tremont, Peckham Rye : March 1th, 1904. 



