34 



Insect Pests. 



References. 



(1) Carpenter, G. H. Injurious Insects, etc., observed in Ireland during the 



year 1906. Eco. Proc. Royal Dublin Society, I., pt. 11, p. 438 (1907). 



(2) Kollar, Vincent. ' A Treatise on Insects,' p. 200 (1840). 



(3) Theobald, F. V. Report on Economic Zoology for the year ending 



April 1st, 1907. p. 25 (1907). 



THE DECEMBER MOTH. 



(Pa'cilocanq)^ populi. Linn.) 



The natural food plants of this insect in its caterpillar stage are 

 poplar, lime, oak, elm, birch, sallow, elder, ash, aspen and whitethorn. 

 Carpenter (1) records it on apple in Ireland, from Newcastle, Co. Clare, 

 where it was very injurious. 



The moth takes its name from its appearing in December, but a 

 few may often be found in the preceding month. It is a common and 

 widely distributed insect, especially in the Midlands and the south 

 and west of England. 



Life-History, Habits, Etc. 

 The moth measures a little over 1^ inch in wing expanse ; the 

 fore wings are a dark purple-red, brown to rusty brown, inclining to 



a brighter hue at the inner corner, 

 where it is followed by a wavy 

 buff line and another curved line 

 across the wing beyond the middle ; 

 the hind wings are paler and show 

 a still paler central stripe. 



In some specimens the ground 

 colour is blackish-brown, and the 

 brighter markings are absent. The 

 thorax and body, as seen in the 

 photograph, are robust and hairy. 

 The moths fly at night in Decem- 

 ber, and are attracted to light, being frequently found in houses and 

 village shops. 



The female apparently lays her eggs at night and they do not 

 hatch until the following March or April (Carpenter) (1). The cater- 

 pillar is very variable ; Buckler (2) figures four quite different forms 

 after the last moult. The normal appearance is as follows : bluish- 

 grey with a double row of grey, black-edged spots along the back, and 

 a row of large black spots on each side, there are also dashes of 



[F. Edendeii. 

 FIG. 21. — DECEJIBKU MOTH 



{Pcecilocaiivpa popuU). 



