114 



THE ENTOMOLOGIST S RECORD. 



wondei- with the writer when he reads of the relative reliability of 

 white, gilt, or black pins, that no extensive experiments appear to have 

 been made with sulphuretted white pins — as suggested by Dr. Knaggs 

 many years ago, which promised to retain the point and temper of the 

 original pin. 



Upon another vexed question, the " Setting of Lepidoptera," we 

 are glad to read among the many valuable suggestions, the candid 

 opinion of the editor that English collectors persistently adhere to 

 the old English style. Most of us find it just as difficult to change 

 our style of setting as to change our hand-writing. Many of the wise 

 suggestions in this chapter will, I fear, fall upon deaf ears, whilst 

 many lepidopterists, perhaps, will feel that they fairly carry out one or 

 other of the methods suggested, but, for the beginner, or for one who 

 is really dissatisfied with his work, the suggestions are invaluable. 



One could, however, wish that an even more emphatic warning as 

 to the removal of insects too soon from the boards were included. The 

 author insists upon it, but is hardly, it seems, in view of the import- 

 ance of the matter, insistent enough. The writer has found sometimes 

 that four weeks drying is not sufficient, and that the body may be hard 

 sometimes long before the wings are absolutely fixed in position. 



One is glad to read again the emphatic statement of the absolute 

 necessity of sufficient " data labels," and only regrets that the editor, 

 whilst advising that every insect should be thus labelled individually, 

 states that the enormous work involved in very large private 

 collections often precludes this, to us, absolute necessity. In the case 

 of these very large collections one can understand that this separate 

 labelling would become quite a labour. Yet printed labels are in the 

 market at quite a moderate price, and can be had cheaply in almost 

 unlimited numbers. The side-labelling sj-stem alone obviously opens 

 such a possibility to error from misplacement, etc., that it should only 

 be allowed in cases where the better and safer plan is either unim- 

 portant, or impossible. 



The last new chapter deals with " Holiday Collecting," and brings 

 home to all readers the advisability of " reading-up " the locality 

 towards which their steps turn, and thus avoid the unpleasant ex- 

 perience of returning without at least some of the prizes of the place. 



Of the remainder of the book, which is largely in its original and well- 

 known form, there is no need to speak, except to note the correction 

 of one or two slips that had got into the earlier edition, and the 

 addition of a few useful incidental data to some of the " hints." — 

 C.R.N.B. 



The Colours of Blue Butterflies. 



By C. NICHOLSON. 

 In the course of an article in The Coimtnj-Sule, some little 

 time ago, the editor, Mr. E. Kay Robinson, invited suggestions as to 

 the reasons for the somewhat varied systems of coloration in British 

 " blues." Being myself too busy at the time to think about it, I let it 

 slide, until, in a recent numl)er, Mr. C. W. Colthrup recorded that he 

 had, on one occasion, noticed a kestrel, and on another occasion a pair 

 of furze-chats, picking male Auriades coriidon off the grass-stems on 

 which they had settled for the night, and he put this forward as an 



