REPORT OF THE ENTOMOLOGIST. 547 



tion * -was too great, being in the neigliborliood of 5, while 4 is only 

 a fair result with white-mulberry cocoons. 



The second week's work in the Washington filature on Osage Orange 

 cocoons gave a rendition of 3.69, and subsequently a result as low as 

 3.65 has been attained. This result was reported to Mr. Serrell, the 

 inventor of the reels used, who, though living abroad, has always 

 taken a lively interest in American silk culture, and his comments 

 thereon are so encouraging that their substance is presented here: 



The rendition from Osage Orange cocoons at the Washington filature is aston- 

 ishing. So far as I know, the only time they have been reeled in France they gave 

 a rendition of nearly 5. That is to say, as reeled in France it took a pound and a 

 third more cocoons to produce a pound of silk than in the work done in Washing- 

 ton. It is fair to say, however, that in France they were reeled in a filature accus- 

 tomed to only the best French cocoons. 



" Be that as it may, the result attained is extremely remarkable, and makes me 

 foresee a prompter outcome from American cocoons than I had supposed was pos- 

 sible. 



Of the silk mentioned several skeins were taken to 'New York and 

 submitted to the most rigorous tests at the Silk-conditioning Works 

 in that city. It is needless to go into the details of the technical re- 

 port made by its manager, but it will suffice to say that this Osage 

 Orange silk gave excellent results, the faults being such as can be 

 cured as our silk -raisers gain in experience. 



The use of Osage Orange as a food-plant has now become quite 

 general in the States Avhere it is plentiful. Some observations which 

 have been made on cocoons raised therefrom may be of service to 

 the raisers who employ it. If two batches of cocoons be taken, 

 raised from the same eggs, the one on the Mulberry and the other on 

 the Osage, they will to the ordinary eye possess no distinct character- 

 istics. The expert, however, can at once and almost unerringly des- 

 ignate the food used in either case, and this on account of the greater 

 degree of satinage observable in those produced by the Osage Orange- 

 fed worms. It was explained in the last edition of our manual that 

 this satinage consisted of an inferior gumming together of the layers 

 of the cocoon, and is made apparent to the eye by the coarser texture 

 of its surface. As a result, the Vv'ater penetrates to the interior, and 

 causes them to sink to the bottom of the basin in reeling, and thus 

 to break off the filament. Although this difficulty has not been 

 proved to be the result of any given cause, still it is generally be- 

 lieved to be due to the insufficient, feeding of the worm during the 

 last days of its life. At this time almost all of its food goes to the 

 formation of silk, and though a worm may make its cocoon if the 

 feeding is stopped five days after the last molt, still it will be weak 

 and commercially useless. In order that it should be strong and well 

 garnished, no food should be spared at this time. The almost uni- 

 versal difference found between the cocoons raised on Osage Orange 

 and Mulberry in this particular leads to the opinion that a greater 

 quantity of the former food is required than of the latter, and that 

 our people have not learned to supply their silk- worms with enough 

 liberality during the days which precede the spinning. 



What has been said above must not be construed as a serious ob- 

 jection to the use of such food, but simply as an indication of how 

 it may be used with greater advantage than at present. On the con- 



*By "rendition" is meant the number of pounds of dry cocoons required to pro- 

 duce a pound of reeled silk. 



