217 



NOTES AND OBSERVATIONS. 



Yellow Colouring of Cocoon of Plusia moneta Result of Moisture. 

 — I do not think that Mr. Bird's theory can be the correct one, as we 

 have records of P. moneta larvas spinning up in similar positions as 

 regards air, light, and moisture, yet producing one permanent white 

 cocoon, and one white cocoon which afterwards turns to a yellow 

 colour. In my opinion the yellow colour is due to some secretion of 

 the larva, which, however, is probably used up in some other way 

 than in colouring the silk of the cocoon, when the larva has not fed 

 for some time before it commences to spin up. Moisture probably 

 hastens the change from white to yellow, and perhaps it may even be 

 necessary for this change ; but still I do not think it is the primary 

 cause. If Mr. Bird's theory is correct, there ought to be a much 

 larger .percentage of permanent white cocoons amongst the second 

 brood than amongst the first, as there is not nearly so much mois- 

 ture in the atmosphere during late summer as there is during late 

 spring ; and as the leaves of Delphinium and Aconitum are both older 

 and dryer, the larva could not obtain much (if any) moisture from this 

 source. In conclusion, I must thank those who have of late been so 

 kind as to furnish me with material and facts relating to this varia- 

 tion, and say that in future I shall feel grateful to any who will kindly 

 give me any facts or material relation to this variation, to enable me 

 to pursue my experiments to an end. — Raleigh S. Smallman ; Carlton 

 House, Heme Hill, July 13th, 1903. 



Apatura iris reared on Willow. — Last spring I obtained seven 

 larvse of Apatura iris, which I supplied with willow, and all pupated 

 successfully. At first I had provided them with sallow, but they 

 refused to eat this for several days, and were consequently without food 

 until the willow was introduced and accepted. — W. B. Polmar ; 

 18, Waverley Road, Cotham, Bristol. 



Plusia ni at Penzance, 1894. — On looking over some undetermined 

 specimens in the possession of the late Mr. W. Baily, of Penzance, 

 in July, 1894, I detected eight worn specimens of Plusia ni. These 

 Mr. B. informed me he had taken recently in one of his gardens. I 

 told him that Prof. Riley had given the name of hrassicm to a »i-like 

 Plusia from its feeding on cabbage, &c. ; whereupon Mr. B. set the 

 neighbourhood to work at larva-hunting, with such success that he 

 bred a considerable number of the required insect. I have not men- 

 tioned this fact, because I considered that the discovery belonged to 

 my friend, to use as he thought fit ; but I see no reason to keep the 

 secret any longer. Mr. Baily told me that, although the larvae of ni 

 and gamma resembled one another, he could easily differentiate the 

 two. I have since seen our national series of ni from all parts of the 

 world, and have come to the conclusion the ni and P. brassicte, Riley, 

 are synonymous. — H. G. Knaggs ; Folkestone, June 19th, 1903. 



Notes on the Liotor Case- Moth. — Without exception the Lictor 

 case-moth' {Entometa ignohilis) is the most plentiful species of case- or 

 housebuilder moth in Tasmania. The Saunders case-moth {Metura 

 elongata) of the mainland does not extend its range to these shores. 



ENTOM. — AUGUST, 1903. S 



