208 Alexander Goodman More. [i869 



CHAPTER XXIX. 



SILKWORM EXPERIMENTS. 



[1869.] 



ABOUT this time the attention of the Royal Dublin Society 

 was being 1 directed to a practical question from which it 

 was hoped that some benefit would accrue to Irish industry. 

 This was the feasibility of cultivating silkworms in Ire- 

 land. The mulberry silkworm was out of the question, as 

 its food-plant will not thrive in the country ; but hopes 

 were entertained with regard to two other species, the 

 Ailanthus silkworm (Bombyx cynthia), and the silkworm 

 of Japan, which bears the quaint scientific name of Bombyx 

 Yama-mai. Mr. W. F. Kirby had lately succeeded in 

 rearing the former in the neighbourhood of Dublin, through 

 all its stages from egg to perfect moth ; but his moths 

 emerged in the ungenial month of November, only to die 

 off, leaving no progeny. This, added to the fact of their 

 food-plant (Ailanthus glandulosa) being a foreign tree, 

 which would need to be introduced on a large scale before 

 an industry could be founded, was sufficiently discouraging 

 to the prospect of successfully acclimatizing Bombyx 

 cynthia. It therefore seemed better worth while to con- 

 sider the case of B. Yama-mai'. 



The larva of this insect feeds on the oak, which seems 

 at first an important recommendation ; while it was also 

 urged in its favour that the Irish and Japanese climates 

 exhibit many points of similarity. Yet in fact the difficul- 

 ties were as great in this as in the other case; for, in the first 

 place, the eggs of Yama-mai hatch out in early spring before 

 the oaks are in leaf; and in the second place, larvaB reared 

 indoors on forced oak leaves were found to die as soon as 

 they had attained full growth, without so much as forming 

 cocoons in which to pupate : thus showing themselves 

 even less adapted to the new environment than the Ailan- 

 thus silkworms had proved in Mr. Kirby's hands. 



