811- K 

 00MBYX 



cult ivat ion. Hut the position of affairs is summed up by the opinion that 

 such .special rents are not general, ami that th.-v have "not really had 

 much effect in bringing about the depression in the silk indust 



Diseases and Enemieu of the Mult,,,^ /A >,,,//. From 186% to 

 1870 Pasteur devoted himself to the study of tin- .li*e*ae* of the silkworm. 

 and tlu> remedial measures which hn recommended have since beet 

 only widely adopted in Knrup.. but throughout the * ilk rearing regions of 

 the world. Even in I mini, thanks to the energy of the late Mr. N. 0. 

 Mukerji and his coadjutors, the selection of seed by the aid of the micro- 

 scope has become an everv-day practice of the ordinary cultivator, who 

 may be said fully to m-o^nis.- th.- value of specially selected seed in the 

 curtailment of disease. A voluminous official correspondence exists in 

 the Annual Reports of the Dept. Land Rec. and Ayri. ana in the Proceeding* 

 of the Govt. of Bengal on the subject of the diseases of the silkworm, 

 especially the papers for 1894 and 1895. 



The chief diseases are : 



(a) Pebrlae. This is known in Bengal M tola, or. in an aggravated form. 

 tali, and characterised by the presence of microscopic nnrnnsolss of an oval 

 shape found within the tissues of the worm, but also in the moth and egg. Though 

 not always fatal, this disease damages the quality of the silk very greatly. Be- 

 sides being contagious, it is also hereditary. The cure u to breed only from egg* 

 laid by healthy females (established by u microscopic examination) and general 

 sanitary precautions to prevent infection. Thin in the worat of all the diseases, 

 and, according to Mukerji, it was unknown in India twenty-five yean ag< > 



42, 53-4). The final conclusions and recommendations deserve to be moat 

 carefully considered and enforced. [Cf. Fisher. Ind. For., xv., 165-7 ; Arbousset, 

 On Silk and Silkworm (Engl. transl.). 1905, 203-5.] 



(b) Flacherie or Qatlne. This is known in Bengal as kola thira or fttalfa, and 

 is characterised by the presence of " chain ferment within the digestive tract 

 of the worm and pupa." The disease is contagious, and to a certain extent 

 hereditary, in that the larvae of moths that show symptoms of flachtrie have a 

 predisposition to the disease. The remedy is as above, namely, for breeding 

 purposes to reject all eggs obtained from moths found by microscopic examina- 

 tion to manifest signs of the chain ferment. [Cf. Mukerji, Le. 05-109; Fisher, 

 I.e. 167-9; Arbousset, I.e. 206-11.] 



(c) Muscardlne. This is known in Bengal as chtina (or chund-ktU) a name that 

 indicates the resemblance to lime and is caused by a fungus, which appears 

 as a white efflorescence on the body of the worm some hour* after it has died 

 of the disease. It is contagious but not hereditary, and though the anV 

 may be so slight as not to interfere with the spinning of the cocoon, the chrysalis 

 almost invariably dies, and thus never emerges as a moth. The disease is spread 

 by the spores produced on the efflorescence, so that the speedy removal of all 

 dead worms is an efficient preventive to a dangerous outbreak. Next to pebrine 

 this does the most harm in Bengal. [Cf. Mukerji, I.e. 74-87 ; Finher, I.e. 167 ; 

 Arbousset, I.e. 195-202.] 



(d) Orasserie. This is the disease known in Bengal as nua. t boffl 

 importance, and is never hereditary. Following mutcardine. it does, however. 

 considerable damage to the worms in Bengal. In Europe it is not looked upon 

 as serious, but in Bengal it becomes often epidemic. It invuriably follows a 

 heavy downpour of rain, if that succeeds to a long period of drought and^ high 

 temperature, especially if the worms be then in their last stage of growth. Worms 

 fed on mature leaf first, and tender leaf afterwards, are liable to take grasurfs. 

 The means of checking the disease ia the propagation of large mulberry-trees. 

 Whenever there is a sudden shower of rain, leaves from trees, not shrubs, should 

 be given. [Cf. Mukerji, I.e. 87-95 ; Fisher, I.e. 169-70 : Arbousnet, l.o. 192-4.] 



(e) The most serious pest is" the Tachinid fly, Tr V rat yv *.< (t 

 Mus. Notes, i., 83-8). This parasite lays its eggs upon the bod* of t 



Those eggs on hatching produce a grub that lives within the body of the worm 

 and finally kills it. [Cf. Mukerji. I.e. 112-21.] 



Influences of Climate. It may be briefly said that in no essential feature are 

 the mulberry worms of India different (as far as liability U 



1UU1 



Pebrine. 



Muscar 

 dine. 



:.. 



of DML 



U-. 



DJLP.. 



Tt.Pt. lit, 



M 



Parasite. 



