I894-] 



THE BRITISH NATURALIST. 



77 



In all other cases Dr. Klein uses glycerine-gelatin, which is, under 

 proper precautions, an excellent embedding material. The object is first 

 hardened by exposing it as a hanging drop to the fumes of the acid for 

 a few minutes. It is then placed in one or two drops of dilute glycerine, 

 and the surplus having been drained off, or the water evaporated, 

 a drop of glycerine-gelatin, previously heated in a test tube, is dropped 

 on by means of a fine glass tube. By this device air-bubbles are avoided. 

 Some objects may be fixed by heating them on the slide up to nearly 

 boiling point, in place of using osmic acid. 



LEPIDOPTERA. 



What Constitutes a British Insect ? — Whilst inquiring " What 

 constitutes a British insect at the present time " {British Naturalist, 

 New Series, page i,) Mr. C. S. Gregson mentions having recently 

 seen specimens of Folia Xanthamista (Hb.), said to have been bred 

 from a female P. Nigrocincta, captured in the Isle of Man. One 

 of my most intimate friends whom I had induced to accompany me 

 to the Island for a few nights, " Nigrocincta larvae hunting,'*' on the 

 rock-bound coast (we having had a most unsuccessful journey), informed 

 me later on that he had the perfect moth offered for sale at one shilling 

 each by a dealer in insects, who said his specimens were bred from ova 

 deposited by a female taken in the Isle of Man. I said " Nonsense ! Isle 

 of Man specimens of Folia Nigrocincta are worth to an honest dealer in 

 British insects many times that sum each, and you having spent night 

 after night in fruitless search for it ought to know that ! " But behold 

 the next time he visited me he brought a rather long series of specimens 

 not like Manx P. Nigrocincta ! which he had bought from his friend the 

 dealer on a guarantee which I have seen, that " they were bred from ova 

 deposited by a female P. Nigrocincta captured in the Isle of Man ! " 

 I merely observed, " This guarantee is hardly likely to make me, who 

 know the Manx form so well, think your purchase Manxmen. 

 My good friend left after comparing his guaranteed specimens with 

 my cabinet specimens, bred by myself from larvae personally gathered 

 (by the light of a lantern) along the rocky coast around Onchan, 

 Douglas, Isle of Man. Since then several correspondents have offered 

 P. Nigrocincta to me in exchange, presumably these is. so-called 

 Manxmen, little knowing that I have been accustomed to visit the Isle of 

 Man several times each year expressly to collect its larvae, and as I have 

 bred a few P. Nigrocincta annually for more than 20 years I think I 

 know the Manx form so well that I cannot be deceived. But I have not 

 answered Mr. Gregson's question " What constitutes an insect British 

 at the present time?" I do not think that these so-called descendants 



