106 Dr. Fr. Meinert on the Ugimyia- Larva. 



frames covered with the same material. The result was 

 this : — 



" 275, say 81 per cent., cocoons pierced by moths. 



" 450, s.ty 53 per cent., pierced by Uji. 



" 135, say 12 (?) per cent., unpierced by either moths or Uji. 



u 30, say 4 per cent., double cocoons. 



" In the presence of these facts the theory that the fly of 

 the Uji deposits its eggs under the epidermis of the silkworm 

 must clearly be given up. Does, then, the fly lay its eggs on 

 the mulberry- leaf ? Is the food the vehicle by which the 

 germ of the Uji finds its way into the silkworm's intestines? 



" . . . . To the kindness of a correspondent who takes a 

 warm interest in the matter we are indebted for the following 

 note: — 'The fly of the Uji is the Ugimyia sericaria (sic), 

 thus named by Hondani.' " 



I may also quote what, according to Mr. C. Sasaki, Mr. 

 G. A. Greeven writes in the 'Japan Times ' of May 4th, 

 1878: — "My experiments have now shown me that the 

 hatching of the Uji takes place in the stomach of the cater- 

 pillar, and that it immediately forces its way through the 

 membrane of the stomach and makes a path for itself to a 

 stigma." 



Mr. C. Sasaki commenced his investigations in 1883, and 

 in the following year he communicated to the American 

 periodical 'Nature' a short preliminary article, u Ulschi- 

 myia sericaria, Kond., a Fly Parasite on the Silkworm " 

 (printed 'Nature,' vol. xxx. pp. 435, 436), which two years 

 afterwards was followed by the fuller account mentioned 

 above. From this last-named treatise I shall try to point 

 out the principal results obtained by Mr. Sasaki concerning 

 the evolution of the Ugimyia sericariw : — (1) The fly deposits 

 its eggs on the under surface of the mulberry-leaves, generally 

 at the end of May. (2) The silkworms being at this time 

 of the year in their third or fourth stage of evolution, devour 

 the eggs — often a great number of them — together with 

 the mulberry-leaves. (3) The eggs remain from one to 

 nine hours in the digestive canal of the silkworm, and the 

 maggots having emerged from the double-shelled eggs, like- 

 wise remain there for from one to eight hours more before 

 piercing through the walls of the canal. (4) Having pierced 

 through the walls of the digestive canal, the maggots directly 

 enter the abdominal ganglia and feed on the ganglion-cells. 

 (5) Having devoured the ganglia, the maggots pass into the 

 body-cavity of the silkworm, and, travelling through the mass 

 of fat, they search for those portions of the tracheal system 



