THE EUROPEAN HORSE-RADISH WEBWORM. 5 
Britain and Ireland. In Canada. it has been reported from Cape 
Breton Island, Little Bras d’Or, Old Chelsea, Quebec, and Nova 
Scotia. In the United States it has been established for many years at 
Cambridge, Mass. Specimens are in the United States National 
Museum and it is noted as occurring in the following localities: 
Albany, Rochester, Kendall, N. Y.; Chester, N. J.; Cambridge and 
North Adams, Mass.; New Hampshire; northern Illinois; Madison, 
Wis.; Washington, D. C.; and Arlington, Va. 
The known distribution is shown in the map (fig. 7). 
NOTES OF OCCURRENCE AND HABITS. 
The moth of this species was collected by the writer in September, 
1898, at Washington, D. C., showing that it has evidently been estab- 
lished in this vicinity for several 
years, presumably feeding on horse- 
radish, though in small numbers, 
since it did not attract attention 
until 1919. 
The records of the Bureau of 
Entomology show that the species 
was received July 27, 1903, from 
Dr Eo elt, Albany, Ns Y- 
June 21, 1913, larve were ob- 
served attacking horse-radish at 
Chester, N. J., by H. O. Marsh. 
Larve under observation on June 
30 burrowed into the soil and spun 
cocoons. The first of these trans- 
formed to pupa July 23, and the 
moth issued August 13, making the Fc. (Distribution of European horse- 
; : ; radish webwerm, 
pupal period in this case 21 days. | 
June 14, 1914, specimens were received from Mr. Francis R. Fox- 
croft, with report that the larve were injuring turnip and radish at 
Cambridge, Mass., and that the leaves had been almost entirely 
devoured in that vicinity. 
July 15, 1919, William H. White, Bureau of Entomology, observed 
larvee on horse-radish at Arlington, Va., and later the writer observed 
this insect in the same locality. 
Eggs which were deposited July 17, 1919, hatched July 24, and the 
larve from this lot, feeding on horse-radish leaves, began to transform 
to pupe August 5. In this case the egg period was 7 days. The tem- 
perature was normal for the season, 64° to 91° F., and averaging 
(iis 
By the third week of July, 1919, all moths from larvee in confine- 
ment had issued from the cocoons; but another lot containing many 
