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The Philippine Journal of Science 
3 023 
ova in two or three different places on the bark of the tree on 
which it feeds. The ova hatch in May or June of the following- 
year. At first the larva is black; after the second molt white 
hairs begin to appear, and it is full grown in about forty-five 
days, when it makes a netlike cocoon, which is commonly known 
as sukashi-dawara. The imago emerges at the end of September, 
when the ova are deposited by the female in the manner pre- 
viously indicated. The larvae sometimes appear in such num- 
bers that they do much injury to the foliage of chestnut and 
walnut trees, but this is profitably counterbalanced to some 
extent by the fact that a kind of catgut named tegusu, used by 
fishermen, is made out of threads contained in the body of the 
full-grown larva and finds a ready sale. 
Local distribution. — Honshu, Musashi Province, Yokohama 
( Pryer ) ; Tokyo, taken and bred September and October 
(Wileman) : Shimotsuke Province, Nikko, October {Leech ) : 
Settsu Province, Kobe, September (Wileman) . Kyushu, Kyushu 
(Leech) : Hyuga Province, Kuraoka, September (Wileman). 
Shikoku, my Japanese collector, informed me that he had taken 
the species in Sanuki Province. Matsumura records it from 
all the Japanese Islands, Hokkaido, Honshu, Kyushu, Shikoku, 
and from Formosa (Taiwan). 
Time of appearance. — Ovum, September and October; larva, 
April to June; pupa, June to September; imago, September and 
October. The imago emerges in September and October and 
then the female deposits her eggs on the bark of the trees and on 
twigs, which pass the winter without hatching. The young 
larvae emerge in May of the following year. Single-brooded. 
As has been indicated by authors previously quoted, a gut, 
named in Japanese tegusu-ito, is manufactured from the silk 
glands or the intestines of the full-grown larva. Those in- 
terested in this subject and in the manufacture of the coarse 
silk, also made out of the strong netlike cocoon, can find further 
details in several Japanese scientific journals . 22 
The following account of the manufacture of tegusu-ito Is 
given by Sasaki . 23 He quotes an extract from a pamphlet, or 
22 Toba, Insect World (Konchu Sekai) 1 (1897) pt. 3, 92-94: SasaM, 
Nihon Jumoku Gaichuhen (Insects Injurious to Japanese Trees) ed. S 
(1910) 92; Sasaki, Dai Nihon NokwaihS (Bull. Jap. Agr. Soc.) (1905) 
No. 294, 15-18; Honda, Dai Nihon Sanshi Kwaiho (Bull. Jap. Sericult. 
Soc.) (1905) No. 160, 1-7; Honda, Dai Nihon NokwaihS (Bull. Jap. Agr. 
, Soc.) (1905) No. 292, 3-11. 
23 Nihon Jumoku Gaichuhen. 
