16 THE CANADIAN ENTOMOLOGIST. 



ON A NEW SCALE-INSECT FOUND ON PLUM. 



BY 1. D. A, COCKERELL, N. M. AGR. EXP. STA. 



Some time ago, Prof. Gillette sent me a few specimens of an Aspidiotus 

 found on plum at Canon City, Colorado, 31st Aug., 1894. They occurred 

 on the fruit itself. He had previously sent the species to Mr. L. O. 

 Howard, who had written that it was apparently new. The material sent 

 was not altogether satisfactory, owing to the fact that the insect occurs 

 solitarily on the fruits, and has to be collected by slicing off bits of the 

 skin. Consequently it is inconvenient to obtain it in quantity, and not 

 very easy to nicely preserve those obtained. However, the discovery of 

 a new Aspidiotus on plums in the United States was a matter of import- 

 ance, and deserved the most careful consideration. It now appears, 

 after some study and correspondence, that the species is really new, as at 

 first supposed, and it may be introduced as follows : — 



Aspidiotus Ifowardi, n. sp. 



9 scale circular, flat, about i^ mm. diam., pale greyish with a slight 

 reddish tinge ; exuviae sublateral, covered, dull orange, secretion over 

 exuvia; easily rubbed off. 

 $ broadly pyriform, orange ; margin of terminal portion thickened, very 

 finely striate, showing a violet colour in some lights. Plates spine-like, 

 sparingly branched. Median lobes very large and prominent, close 

 together but not contiguous, obliquely truncate, slightly crenate. 

 Second pair of lobes small, broad and low. Third pair practically 

 obsolete. There are conspicuous " wax ducts." 



This species belongs to a series with circular or nearly circular $ 

 scales ; and more elongated, somewhat oval 1^ scales. The covered 

 exuviie are orange or reddish, and easily exposed by rubbing. The 

 median lobes of the ? are large, the others comparatively small, or 

 obsolete. Such species are A. per7iiciosus, Comst., A. ancylus, Putn., A. 

 punicce, Ckll., A. ostreceformis, Curt. 



In perniciosus, one does not find the same array of_ plates as in 

 Howardi, and there are the characteristic " incisions" between the lobes. 

 Moreover, perniciosus always lacks the grouped glands. 



Turning now to ancylus, we find a species with grouped glands when 

 mature, but presenting also the " incisions " as in perniciosus. It has 

 not, either, the same arrangement of plates as Howardi. A. jug/ans-regife 

 is clearly out of the question, by superficial appearance alone. The West 



