7884 Insccls. 



Plumules in the Wings of the Genus Pieris. — At a late meeting of tl)e Manchester 

 Literary and Philosopliiciil Society Mr. John Watson read a paper " On ceviain Scales 

 of some Diurnal Lepidoptera," in which he recommends a new and c^irefnl study of 

 this subject. In some ijenera peculiar scales, called plumules, have long^ been known ; 

 but examination with the binocular microscope shows that they are not fiat, like ordi- 

 nary scales, but cylindrical and hollow. Tiiey have been found only in certain (genera 

 (named in the paper) at present, and on the males alone; they possess generic resenri- 

 blances and si)Kcilic differeiicis, each species displaying its own distin<(nishin{^ variety. 

 One of great beauty and noveltv, found only on two African butterflies, Pieris Agathina 

 and P. Chknis, was described, and some very fine drawings of it, by Mr. Joseph Side- 

 botham, were exhiltiled, and also other figures by liim of about one hundred species 

 never figured before. The names and habitais of the insects were given, and the author 

 pointed out the value of these scales for the assistance of the scientifio entomologist in 

 arranging genera and species. He then entered into the question as to their probable 

 use as air-vessels in the economy of the insects possessing them. The chairman 

 remarked that the scales of the Lepidoptera may |)rove as valuable in determining 

 species as the .scales of fishes. Mr. Sideboiham alluded to the value of the binocular 

 microscope in defining the cylindrical form of the plumules, and described the mode 

 of finding them in situ by breaking the wing. Mr. Watson staled that soine of Mr. 

 Sidebothain's. excellent drawings were taken under the eighth objective, magnifying 

 750 diameters. Mr. Waison further said that he had examined the wings of 400 spe- 

 cimens of the Pa|)iliiinidiB, but had not discovered any plumules in that family. He 

 also alluded to several so-called species from South America, of which no males have 

 yet been found, others of which no females have yet been dit-covered, and suggested 

 the possibility of some of these being male and female of the same species, to ascertain 

 which careful examination of the scales might be useful. Mr. Watson exhibited a 

 number of mounted specimens of the plumules, and four Ciises of the Lepidoptera, 

 from whose wings the ninety-ei^ht drawings figured by Mr. ^idehotham were taken. 

 They were principally Pieris, Anthocharis, Euterpe and Eronia. Amongst the former 

 were some new and unnamed species from Celebes, with rare specimens fiom Vene- 

 zuela, Quito, East and West Indies, Africa and other piirts of the world. — ' Quarterly 

 Journal of Microscupicnl Seiencs' for January, p. 69. 



[It is interesting to see this, the oldest of all entoracdngital iniiuiries, again 

 revived; a similar attempt was made in 1828, when the plumules of fifty-four species 

 of male Pierides were figured, and the objects themselves examined at a meeting of 

 the Entomological Club. The idea thai these plumules had ever been considered 

 " flat'' is new to me. — Echvard Newman'\. 



Viscid Lines in a Spider's Web. — As I have, although veiy casually, alluded in 

 this paper to the large g.irden spiders, I may, perhaps, be allowed lo mention a fact 

 connected with them which came under my notice about the same time. It is well 

 known that in all geometric spider webs the concentric lines, with the exception of 

 those in the very cen.re, are must beautifully dctted with a viscid substance, to aid in 

 the capture cpf insects. Mr. Blackwall has, I believe, compiUed that there are mora 

 thiin 100,000 of these gummy drops in a web which is made in aViout hiJf an hour; it 

 has always, therefore, been a puzzle in my own mind how this pait of the process was 

 effected, and as I had been unable to find any one who could gi\e me a satisfactory 

 txplaiiat on, I thought I «ould carefully watch a spidtr during the operation, when, 

 wiih orly a pocket lens, I could dislii,cily see that the viscid line.---, us lirst drawn I'ruin 



