LEPIDOPTEEA. 243 



of all sorts, not less useful than the silk derived from this tree." 

 Olivier de Serres proves in this memoir that the second bark or, 

 liber of the mulberry tree contains a fibre capable of replacing 

 hemp or flax, and he describes the processes by which this may be 

 obtained. The processes which had been proposed by Olivier de 

 Serres in 1603, were resumed in the Cevennes a dozen years 

 ago by M. Duponchel on the one hand, and on the other by 

 M. Cabanis,* who operated on bark instead of taking the whole 

 of the wood of the mulberry tree. But none of these attempts 

 have given any good results up to the present moment. 



The various diseases which, for the last fifteen years, have 

 been so fatal to the mulberry silkworm, have suggested the idea 

 of acclimatising in Europe other silk-producing Bombyces, if not 

 with the view of superseding, at least as auxiliaries to the mul- 

 berry species. The genus Attacus has furnished these auxiliaries. 

 Among the species which have, in this respect, the greatest 

 claims to our attention, we must place in the first rank those 

 which feed upon the leaves of the oak tree. Indeed, the trees 

 which can be made use of for their cultivation are very numerous 

 in Europe, and, moreover, the silk produced by these worms appears 

 to possess superior qualities. 



There are three oak-feeding species of the genus Attacus. They 

 are Yarna-Mal, Pernyi, and Mylitta. 



The silk of Yama-Ma'i is as bright as that of the mulberry silk- 

 worm, but a little less fine and strong, and occupies the first rank 

 after it. If we could succeed in acclimatising this species it would 

 supply any deficiency there might be in our crops of ordinary 

 silk. 



The eggs of the Attacus Yama-Mal were brought from Japan, 

 where this worm is reared, conjointly with the mulberry silk- 

 worm, in 1862. The larvae hatched at Paris, in 1863, were 

 green, of a great size, remained in that state eighty-two days, 

 and were easily reared. Their cocoon resembles that of the 

 mulberry species. It is composed of a beautiful silk of a silvery 

 whiteness in the interior, and of a more or less bright green 

 on the exterior. The moth is very large and beautiful, of a 

 bright yellow colour, approaching orange. 



* See our " Annee scientifique," 7e annee, p. 432. 

 R2 



