120 THE entomologist's record. 



that, if a minimum of temperature were taken for each species a certain 

 sum total of heat above this minimum would produce emergence. Mr. 

 Fenn wished to know how it was, if this quantity of heat were fixed, 

 that of many pupa^ kept under precisely similar conditions of tempera- 

 ture, some would emerge one year and others would not do so for 

 another year, the latter, of course, absorbing much more heat than the 

 former. Mr. Tutt suggested that it seemed that the influence of tem- 

 perature in producing rapid development appeared to depend on one 

 fundamental principle : — The insect in the pupa-case undergoes a slow 

 process of development. If a certain point in this development be 

 reached, then increased temperature at once influences the pupa, and 

 rapid emergence is the result ; but if it be not reached, then increased 

 temperature is inoperative in this direction until such point be reached. 

 Mr. Adkin brought the discussion to a close by remarking, that of two 

 lots of Ejtpithecia vitli^ata pup^, one lot kept for some months during 

 the winter in the house, and the other out of doors, the latter, although 

 they must have absorbed much less heat, emerged a day or two before 

 theothers, and that the indoor influence had apparently been inoperative. 

 July loth. A few very interesting exhibits took place. Mr. Jager 

 exhibited a fine series of Dianthcecia capsophila from the Isle of Man. 

 Specimens of the same species (more resembling carpophaga) from 

 South Wales, a very dark Diantluvcia ccesia also from the I. of Man ; 

 Mr. Wellman, a very fine box of DianthtEcicE — comprising cucubali, 

 carpophaga, capsophila, and conspersa from different Scotch, Irish and 

 English localities ; also a very long series of Eupithecia reclangiilata 

 var. ?iio7-osericeata irom. Streatham ; Mr. Croktir a long series of iVf?Az 

 cucullatella with black vars. from the London District ; Mr. Howard 

 Vaughan, an interesting box of Scotch specimens including Melitcea 

 arte;)iis, Canoiiympha davus (undersides), several Eudoreic {Scoparice), 

 2 strange looking Procris, apparently jArZ/Vd'y but with antennae somewhat 

 resembling those oi globularia^, Mr. Briggs, a box of Procndce to compare 

 with Mr. Howard Vaughan's specimens ; Mr. Gerrard, Psyche vilosella 

 (case) and Eulepia cribrii/n ; Mr. Adkin, variable Coremia propugnata 

 and Eupithecia ?ianata, the latter varying considerably within certain 

 limits. A discussion re vars. caliiinaria and curzoni took place and 

 Messrs. C. G. Barrett and Tutt gave decided opinions as to curzoiii 

 being an extreme var. of E. satyrata ; Mr. Joy specimens of Aleliana 

 ^amtnea, N'. cilialis, and M. arundinis recently captured in Wicken Fen \ 

 Mr. Jenner Weir, specimens of Vohicella bombylatis showing mimicry in 

 the direction of the Bouibi, on which it is parasitic ; and Mr. BiUups 

 specimens of Trichiosoma betuleli and its parasite bred from cocoons 

 taken at Mitcham. Other minor exhibits took place. Very little 

 discussion took place on ihe exhibits. — Ed. 



[The labour of writing out an extra Report of this Society for the 

 Record is too great for the Secretary. The Council agreed that we 

 "should have copies of the Reports when they were sent to other 

 Magazines." This means that some would be 6 or 8 weeks late in 

 publication. The Reports will therefore be printed or left out according 

 as to whether it is convenient or not for me to attend and report the 

 meeting. I make this statement in order to show our subscribers who 

 are members of the South London Society, that I have done my level 

 best to publish the Reports if I can get them up to date. — Ed.] 



