502 



a green fluid as if they had been poisoned by insect powder or tobacco. 

 Some individuals also developed dark patches on the body. As these 

 symptoms differed from those of any known disease of silkworms, 

 the author investigated the matter and succeeded in finding the cause. 

 His attention was first drawn to the fact that those who were handling 

 mulberry leaves were suffering from severe irritation caused by 

 caterpillars of the gold-tail moth, Arctornis chrysorrhoea, L. {Porthesia 

 similis. Fuess.). Experiments were made on batches of silkworms fed 

 on mulberry leaves that had pre^^ously been in contact with these 

 caterpillars, while others were fed on clean leaves as a control, and it 

 was clearly demonstrated that the symptoms observed were due to 

 the presence of these caterpillars. The urticating hairs of the cater- 

 pillar may be eaten by the silkworm or they may become attached to 

 its body by contact. In the former case vomiting is caused, while in 

 the latter dark patches appear on the body. There can be little doubt 

 that the so-called " black-patch " disease of sill\ worms, the cause of 

 which has hitherto been unknown, is due to the urticating hairs of 

 Arctornis chrysorrhoea. 



NisHiKAWA (I.). Sanji Hantenbyo no Genin to odorokubeki Kinkemushi 

 {Porthesia similis, Fuess.) no Dokumo Sayo. [The Cause of 

 " Patch " Disease of Silkworms and the terrible Urticating Hairs 

 of the Gold-Tail Moth Caterpillar, Porthesia similis, Fuess. J — 

 Sarigyo Shimpo [Journal of the Silk Industry], Tokyo, no. 305, 

 1st August 1918, pp. 998-1003. 



The author has come to the conclusion, independently of the 

 experiment in the previous paper, that the so-called " patch " disease 

 of silkworms is due to the urticating hairs of the caterpillar of the 

 gold-tail moth, Arctornis chrysorrhoea {Porthesia similis). Dark 

 patches are said to occur both in young and mature silkworms, though 

 in the author's experiments only individuals from the fifth instar 

 onwards were used. Dark patches may be similarly caused on 

 Theo'phila mandarina, Moore, and Zamacra albofasciaria, Leech. 

 The intensity of the affection varies among difTerent races of silkworms, 

 the endemic race being rather susceptible. 



NiSHiGAKi (T.). Kurimushi no Riyo. [Utilisation of the Chestnut 

 Caterpillar.] — Sangyo Shimpo [Journal of the Silk Industryl. 

 Tokyo, no. 305, 1st August 1918, pp. 1007-1009. 



The author states that Uchida of the Tochigi Prefecture has invented 

 a method of preparing a kind of thread from the old cocoons of the 

 Saturniid Moth, Dicfyoploca japonica, Butler. He has obtained a 

 special permit from the Imperial Government and contemplates 

 making a textile fabric from it. The moth is well-known as an injurious 

 insect that feeds on many forest and orchard trees, such as chestnut, 

 camphor, pear, apple, etc. The cocoons are collected by means of 

 a long stick" with an iron hook on the top. As is usual in the case of 

 insects under natural conditions, the harvest of cocoons may fluctuate 

 greatly from year to year so that the possibility of continuous 

 mamifacture may be expecterl to be rncertain. The thread made 

 is also used as hair for dolls. 



