57 



The Destructive Potato Moth.* 



By J. Gr. O. Tepper, F.L.S., Corr. Memb. 



[Read March 1, 1881.] 



Some thirty years ago, when practically connected with 

 farming, I oljserved that during the first years the potato 

 tubers kept well, and the loss through rotting was but triiling. 

 But after that a change took place, and putridity attacked 

 them in an unusual degree, and even many of those that 

 appeared healthy were found, to the astonishment of the per- 

 sons concerned, when brought to the test, to contain a number 

 of small caterpillars living in tortuous galleries tunnelled out 

 by them. These, which were only marked on the exterior by 

 small rough projections scarcely discernible to sight or touch, 

 eventually became putrid and affected all the adjoining tubers, 

 thus causing in a comparatively short time the destruction of a 

 large proportion. These remarks are intended to show that 

 the pest I refer to was little known at first, and that it was 

 either introduced, or that the culture of the potato plant 

 supplied some previously scarce native insect Avith such abun- 

 dance of food as to produce its excessive increase. As far as 

 my continued observation goes, the same insect designated 

 above as the " Destructive Potato Moth," causes now, in its 

 immature form of the caterpillar or grub, the destruction of 

 hundreds of tons of potatoes every year by boring them, and 

 thereby inducing putridity. During late years I have scarcely 

 ever been able to get half a dozen pounds without finding a 

 considerable percentage more or less affected in this way. 

 Unless proper means are adopted to check this growing evil, 

 the chances are that potato cultivation will suffer so much as 

 to become unremunerative, and therefore more and more 

 restricted in area. 



As the first step in attempting to combat effectually an 

 existing evil is to learn as much about it as possible by close 

 observation, I was resolved to do as much in this instance as 

 circumstances would permit, and the following remarks will 

 show the results obtained : — 



* Specimens submitted to Mr. Meyrick, M.A., of Sydney, were named 

 by him Llta solanella, Boisduval — the insect which formed the subject of a 

 paper in Lin. Soc, N.S.W., IV., p. 112, 1879.— Edit. 



