1^.10.] 319 



posteriorly a large white blotch with dentate edges occupies the middle of the scale 

 longitudinally, lying in a very slight depression, of which the margins are in the 

 least degree obtusely raised ; on each side of this and distinct from it is a broad, 

 dentate, white patch, which does not extend to the lateral margin and reaches 

 almost to the anal cleft. Length, 5 ; breadth, 4 ; height, 3 mm. 



Larva. Ochreous, oval, rounded at both ends, margin with very short hairs ; 

 anal cleft wide and long, the two setiferous lobes within the cleft not extending 

 beyond the circumference of the body ; mentum entire, not articulated. Antennae 

 of 6 joints, with long hairs, one of them longer than the others on the 3rd, 4th and 

 5th joints, and one still longer on the 6th. Legs with long, slender, knobbed 

 digitules, two longer than the others. These characters, which are quite those of a 

 Lecanium, and not of Kermes as might have been suspected from the rotundity of 

 the ? scale, have been verified by Mr. G. S. Saunders. 



On May 12th, 1S90, I received from Dr. Chapman, of Hereford, 

 three examples, on last year's oak-shoots, of the immature form de- 

 scribed above, which differ essentially from the perfect state, and it 

 has not been noticed before. At the same time I also received some 

 precisely similar scales on oak-shoots from Mr. R. Newstead, Chester. 

 In a week all had become brown, the markings had disappeared, and 

 the scales had collapsed. 



On June 10th Dr. Chapman sent on oak-shoots some of the 

 mature scales, a few of them containing eggs. These hatched on 

 June 23rd, and the larvae produced are described above. It is curious 

 that none of the sound mature forms examined possessed antennae or 

 legs, these apparently having become atrophied when they had served 

 their purpose, just as they always do in the Diaspina. This also was 

 Signoret's experience with some species of Lecanium and Kermes, but 

 was not so generally. 



The male, bred by Mr. Xewstead in May, from an ordinary glossy 

 scale, is quite of the generic type, and presents no special specific 

 characters, as indeed is often the case in this genus. 



From mature 9 scales received this year a quantity of Hymeno- 



pterous parasites emerged : some of these I sent to Mr. L. 0. Howard, 



of the Entomological Division of the United States Department of 



Agriculture, and he writes respecting them : — 



" I find two parasites. The larger ones are the females of a variety of Blasto- 

 thrix sericea, Dalman. They differ from the normal form in that the last one or 

 two funicle joints of the antennje are brown instead of yellow-brown. The smaller 

 specimens with the long hairy antennse are males of the same species. There were 

 13 females and 24 males in the quill, and also two specimens of a species of Paeh.y- 

 neuron which I cannot determine specifically. The habits of Pachyneuron have been 

 disputed, but the truth is that there seems to be little uniformity of habit in this 

 genus. Species have unquestionably been bred from larvae and puparia of Syrphid 

 flies, whilst others have been bred from Aphids and Coccids." 



153, Lewisham Road, S.E. : 



October nth, 1890. 



