28 



unlikely may be followed by a third in Arkansas. Our correspondent 

 writes us that this insect is very destructive to fruit trees in bis county. 



THE THISTLE CATEKPILLAll IN WASHINGTON TERRITORY. 



]Mr. E. O. Scbwiigerl, of Naomi, Kitsap County, Wasb. Ty., sent to us 

 tbe middle of June specimens of the larvte of tbe common Tbistle 

 Buttertiy (P//m?Mm cardni) iufestini«- tbistles and nettles there and 

 wbicb be bas not beeii able to find on any other plants. This is a com- 

 mon butterfly, wbicb is known to feed on the tbistle tbe world over, 

 and belps mucb in keeping tbis noxious plant in cbeck in thistle in- 

 fested localities. Our correspondent writes us tbat 90 per cent, of tbe 

 tbistles around Seattle are infested. Tbe birvaj attack first tbe bead 

 or young sboots, eating out tbe tlower buds, and tben work down inside 

 tbe stems, tbus effectually destroying the seed crop. Birds do not eat 

 tbese birvje on account of tbeir sbort, sbarp spines. 



THE CECROPIA SILK-WORM AGAIN. 



In Insect Life, for November (page 155), was mentioned the great 

 abundance of tbe Cecropia near Calaway, Nebr. As we wisbed to ob- 

 tain some of tbese cocoons, Miss Brown was written to and at tbe same 

 time cautioned not to take any old cocoons, as the abundance whicb sbe 

 referred to migbt be due to tbe accumulations of many years. In ber 

 reply sbe says: 



A little boy collected luo about balf a bushel, but wheu I assorted tbeiii I iouud 

 tbat about half of them were poor. A good many Avere stuug aud filled up witb 

 small grubs of some other insect, aud others were last year's cocoons. I suppose you 

 know that tliere is not much timber here, excepting where it has been set out and 

 planted; and it is only on the cultivated box-elders, and then only iu certain locali- 

 ties, that the cecropia silk-worm is found in numerous quantities. 



Under date of December 16, 1888, M. Natalis Eondot writes us : 



You notice, iu No. 5 of INSKCT Life, the remarkable abundance of Cecropia in one 

 of the counties of the State of Nebraska, Miss Clara E. Brown having asked if the 

 cocoons had any commercial value. To this question you replied that on the account 

 of the difficulty in reeling the filament of the cocoon it could hardly be used indus- 

 trially. This is true; but we may well ask if these cocoons may not be used for 

 spinning into schappe (spun silk) or for articles of fantaisie. I do not know whether 

 these cocoons have been studied from this point of view ; in France at least no serious 

 trial has been nuule of them, though I have had some samples of them combed as a 

 matter of pure curiosity. The first questiou to study is that of the quantity of these 

 cocoons. Miss liiown has, iierhaps, personal reasons for complaining of the damage 

 done by these wild worms; but it is possible that in reality the product in cocoons' 

 would be very light. It would be important to know how many of these cocoons 

 could be obtained ; for, in order to make a proper test, it would he necessary to have 

 several pounds. This Cecropia is little known to us, and I find iu fact that we even 

 have no specimens of it. It would be interesting to have some, at least some of the 

 cocoons, such as are found attached to trees, and some of the moths. In examining 

 my notes I find that I saw, some years ago, cocoons and moths of certain species, one 

 of which was very probably the Plaiystiniia vccropia, while the others were of one or 

 two species very similar to it. Were they hybrids of tiie Cecropia? I do not know. 

 As the Cecropia is abundant in the United States you ought to know whether it is of 

 a unique species or whether there are others allied to it, 



