11 



In the estimates made by the Government Engineers for the clearing 

 of Bayou Pierre, the priueipal item has been the cleaning out of this 

 lower raft. The removal of this portion of the raft is not now neces- 

 sary, however, as the water has made for itself a new channel through 

 Bennett's Bayou on the west. This natural change in the course of the 

 stream, and the slow but constant breaking up of the remaining and 

 less stable portions of the raft, will make the clearing of Bayou Pierre 

 at the present time comparatively inexpensive. The raft, even if left 

 to take its own course, would in time go out of itself, and if the work of 

 loosening that portion above Bed Bluff should be undertaken in time 

 of high water, the bayou might be freed of logs with little difficulty. 

 Taking the estimates in the report above cited as a basis, $-'5,000 would 

 probably cover the expense of removing such portions of the raft as is 

 now necessary. The final disposition of the material of the raft would 

 occasion some difficulty. It could, however, be directed into Lake Can- 

 nisnia and secured there in still water, beyond the reach of the current 

 of the Bayou Pierre, which crosses this lake. If this were done the 

 gnats would not breed on the raft, and in a short time, by the accumu- 

 lation of sediment and growth of plants, it would become entirely solid- 

 ified, as is now the case in its lower portion in Bayou Pierre. 



The utility of the stream as a water-way and the reclaiming of much 

 valuable land which would result from such improvement, while having 

 no direct bearing on the question at issue, may still be mentioned as an 

 additional reason for removing the obstruction of logs, if this is thought 

 not to be warranted by the presence of the gnats alone. 



NOTES OH NOISES MADE BY LEPIDOPTERA. 



By Henry Edwards. 



The article by Mr. A. H. S win ton on " Stridulation in Vanessa an 

 tiopa" published in the last number of u Insect Life," Yol. I, p. 307, 

 has directed my attention to the subject, and I venture to add a few 

 notes on this interesting phase of entomological study. It is not alone 

 among the Vanessas that antiopa has the power of making a sound, for 

 many years ago in England, when I began to collect butterflies and 

 moths, I observed that the beautiful Vanessa io, the favorite of every 

 young entomologist, gave out a slight rasping sound when many speci- 

 mens were flying together, or when a male was in hot pursuit after the 

 opposite sex. But the sound was very slight and could only be distin- 

 guished when " all around was still," and when there was no conflicting 

 influence to deaden the insect's expression of love. The projecting vein 

 which is shown in Mr. Swinton's cut is also quite apparent in V. io, 

 and probably isa character of the whole of the genus, Still more remark* 



