260 [April, 



Note on Acherontia Atropos in Caithness. — In March, 1877, a correspondent of 

 the Ent. Mo. Mag. made enquiry about the occurrence of Acherontia Atropos in 

 Caithness. In the Ent. Mo. Mag. for the following month I mentioned the only- 

 instance then known to me. Perhaps it may interest Mr. Sandison to hear that it 

 has been taken twice since then, and on both occasions by chance observers. In 

 August, 1877, a specimen was found at rest in the daytime in a grass field adjoining 

 one of potatoes, at Billster, near Wick ; and in August, 1879, another was startled 

 out of ivy at Barrock House, in the parish of Bower. No doubt the insect occurs 

 occasionally throughout the county. — L. D. Dunbar, Wick, N.B. : Feb. 17th, 1882. 



Further note on Tortrix Lafauryana. — I have just had the pleasure of ex- 

 amining a series of variations of both sexes of Tortrix Lafauryana, Kagonot, kindly 

 lent for the purpose by Mr. Atmore, and am able to add a few words to my note on 

 the species (ante p. 17). In the males the range of variation here seems to be from 

 the usual yellowish or pale ochreous colour to a bright fulvous, the markings slightly 

 darker, or even almost obliterated. Females either very pale ochreous, greyish- 

 ochreous, or dull brownish-red, in all cases having the fore-wings crossed by nume- 

 rous irregular, delicate, faintly darker lines, something as in the female of Lozotcenia 

 rosana, giving the wings a faintly reticulated appearance. This also occurs, but more 

 faintly, in the males. 



By good fortune, at the same time, my old friend, Mr. Machin, has sent me a 

 pair of Tort rices reared by him from Stat ice limonium, which are clearly L. latior- 

 ana, Wilk. (a variety of L. costana), the female of which resembles the paler females 

 of Lafauryana in shape, size, and colour, but is entirely destitute of the delicate 

 reticulations of that species, and is thus easily distinguishable. — C. Gr. Barrett, 

 Pembroke : February 2oth, 1882. 



On the colouring matter, Sfc, of cocoons of some of the silk-spinning Lep idoptera. 

 — I have been much interested in reading an article in the " Journal of Science " for 

 last month (February, 1882), by Mr. J. W. Slater on "Silks and Silkworms," and 

 my attention was especially caught by the part where the statement of Major 

 Coussmaker, who has studied the large Indian silk-spinning larva?, is quoted to the 

 effect that by opening cocoons at various intervals he had convinced himself of the 

 fact " that when the caterpillar has left off eating and begins to spin, it voids the 

 food remaining in the alimentary canal, first of all in a more or less solid form and 

 of a dark colour, but after it has become fully enveloped in the cocoon, the excrement 

 comes away as a light-coloured liquid, the hue and consistency of which depend 

 upon the amount of vegetable matter not previously evacuated, and the amount of 

 lime, carbon, and ammonia present :" and he considers the use of this excrementi- 

 tious deposit is to harden the cocoon, but at the same time it stains the silk, and it 

 is from this point of view chiefly that he takes notice of it. Now to me at first, 

 when I recollected the invariable habit of larva? to empty the intestine of food before 

 commencing the cocoon, this statement seemed sufficiently startling ; but presently 

 the yellow powder in the cocoon of Clisiocampa neustria came to mind, and could 

 not be accounted for as emanating from the spinnerets of the larva ; so I turned to 

 Kirby and Spence, and found of course that they had not omitted to speak of this 

 habit, but after mentioning it as belonging to C. neustria and Liparis salicis, they 



