THE CANADIAN ENTOMOLOGIST 53 



NEW BRITISH COLUMBIA TUSSOCK MOTH, HEMEROCAMPA 



PSEUDOTSUGATA. 



BY J. MCDUNNOUGH, PH. D. 

 Entomological Branch, Ottawa.* 



For the past few years a species of tussock-moth has been reported as 

 damaging the douglas fir in certain districts of British Columbia; it was de- 

 termined by Mr. E. H. Blackmore in the Report of the British Columbia Pro- 

 vincial Museum, 1918, p. 12, as Hemerocam pa vetiista gulosa Hy. Edw. and a 

 figure of a rather rubbed cf was given on Plate 1. 



An account of the extent of the devastation was also given by Mr, W. B. 

 Anderson, in the Agricultural Gazette, 1919, VI, 139. 



In the spring of 1920 I received a number of egg-masses of the species, 

 collected by Mr. W. B. Anderson, the original discoverer, at Chase, B. C. From 

 these I was enabled to breed a limited number of adult specimens; the young 

 larvae on hatching were offered hemlock and pine, douglas fir at the time not 

 being available ; a large number refused to eat and perished, but a few nibbled the 

 blossom-buds of hemlock and fed on these until half-grown when they were 

 transferred to douglas fir, a tree of this species having been located at the Experi- 

 mental Farm. The moths emerged in the first week of July during my absence 

 from Ottawa, an earlier date than that given by Mr. Blackmore in his account 

 of the species, but probably due to more or less forcing of the young larvae during 

 the early spring. 



From my present knowledge of the early stages and of the adults I cannot 

 agree with Mr. Blackmore that the species is gulosa Hy. Edw. This species 

 was described in Papilio I, 61, in a paper by Mr. Edwards dealing with the 

 Pacific Coast species of Orgyia (Hemerocampa). In this paper vestiista Bdv., 

 a species described very briefly from a cf specimen from California which is 

 possibly still in the Oberthur Collection at Rennes, France, and which has 

 certainly never been satisfactorily identified by American systematists, was 

 limited to a lupine-feeding larva of the San Francisco Bay region, whilst the 

 name gulosa was proposed for an oak-feeding larva which was found abundantly 

 throughout the foot-hills of the northern Sierras. Both larvae were described 

 rather inaccurately and inadequately; roughly speaking, apart from the difference 

 m food-plants, the main points of distinction are apparently to be found in the 

 color of the dorsal abdominal tufts; in vetiista the tufts on abdominal segments 

 I-IV are described as being whitish drab at base tipped with chestnut-brown; in 

 QiiJosa tuft I is blackish, the other three tufts being white; the dorsal tuft on seg- 

 ment VHI is yellow tipped with black in vetiista and black in gulosa. 



In Psyche VI, 438 (1893) Dr. H. G. Dyar gives a detailed description of the 

 early stages of gulosa ; his description of the 3rd and 4th larval stages corresponds 

 well with Edwards' larval description ; in full grown larva; Dr. D\ar states of the 

 tufts that they are "coloured a silvery-grey," in some specimens blackish or even 

 black on the crests, but white on the sides, in others nearly all white." He further 

 is of the opinion that Edwards confused the moths resulting from the two species 

 of larva and that the description given by Edwards of the adult cf vetusta should 

 apply to gulosa and vice-versa: to avoid confusion he limits the application of 

 *Contribution from the Kntv^mc lexical branch, Department of AgriculturP, Ottawa. 

 March, 1921 



