30 



THE CANADIAN HORTICULTURIST. 



the Cecropia Caterpillar, The larvae of tliis 

 fly are of a translucent yellow color, and 

 when mature, eat their way out of their 

 victim and change to the chrysalis state 

 under the oround. Tlicre are also two 



FIG. 6. 



smaller species of parasites, 

 known as Chalcis flies, which 

 are destructive' to this insect; 

 one of these, (Chalcis Maria,) 

 is shown in Fig. 7, much enlarged, 

 the cross lines at the side show- 

 ins the natural size. 



MILDEW ON THE BLACK CUEEANT. 



BY REV. W. STEWART DARLING, TORONTO. 



I should be glad if in the next number of the Horticulturist the 

 editor would say whether he has seen or heard of a sort of blight or mil- 

 dew which here has fallen on the black currants, and which, if it spreads^ 

 will put an end to tlie culture of that fruit. I have some beautiful 

 black Naples bushes from which I have never had any perfect fruit • 

 altliougli a man who knows something about it said the other day, I 

 ought to have half a bushel of currants from each tree. Soon after the 

 foliage is fully developed, I observe here and there thdt the leaves begin 

 to assume an upright tendency around the edges ; underneath I find 

 an almost invisible film, which however is so slight that I can assure 

 myself of its presence only by passing my fingers over the under side 

 of the leaves, after which there is a perceptible "stickiness," which 

 contact with healthy leaves does not produce. This continues to in- 

 crease till the film becomes white, and passes over on' to the upper side of 

 the leaf in the form of mildew. This subsequently becomes brown, 

 and the leaf, or part of it, will crumble as if scorched with fire. The 

 power of the leaf is evidently destroyed before this stage; the fruit is 

 arrested^ in its growth, and even that which is tolerably matured is dry 



