the female scales are elongate, pointed at one end; nor by Chionaspis, 
which have the female scales more or less pyriform in outline, and the 
male scales linear, soft, white, with the usually yellow larval skin at 
one end; nor by Diaspis, which has the female scale much like Aspidio- 
tuSjbnt the male scale like Chionaspis. 
We maybe misled by Diaspis if, as 
sometimes happens, we find only fe- 
male scales. In Europe two similar 
species, one an Aspidiotus (A. ostrecc- 
formis), the other a Diaspis, were long 
confounded under one name. The 
Q Aspidiotus piricola recently described 
•s. . . .. , . » by Del (luercio, which L have recog- 
cai^*;* . nized in specimens found on Prunus in 
Fig. l.-lHaspis piricola: characters offe- California is said by Berfese to be ill 
male (original). J 
reality the Diaspis just mentioned sec 
tig. 1). I formerly saw only female scales, but have lately received those 
of the male, which are as in Diaspis. A figure is given so that the insect 
may be recognized by those who conic across it. 1 
THE STUDY OF THE SCALE. 
With an ordinary pocket lens the characters of the scale can be made 
out. The following table may be found useful: 
A. Scale quite convex, about Hinm. diameter, whitish with an cchreous or grayish 
tint, with a contrasting dark spot marking the exuviae, which are toward 
the side. 
1. Scale somewhat translucent, so that it lias a decided orange or yellowish 
tinge when covering the living insect; a species not extending above the 
lower austral zone A. rapax Comst. 
2. Scale more opaque, thus appearing whiter; a species common in the upper 
austral zone, found mainly on poplars and willows 1. convexus Comst. 
'Attention is called to the four rudimentary Lobes on each side, besides the largo 
median ones, which are dark-colored. There is a well-marked median or anterior 
group of ventral glands, numbering at leasteight. As Mr. A. ('. F. Morgan remarked, 
in Aspidiotus Mtreceformis the inner lateral margins of the median lobes are produced 
to encircle the anus, while there is nothing of the kind in the Diaspis. Then; has 
been some question as to what name this Diaspis should bear. Fitch's Aspidiotus 
circularis (Tr. N. V. Agr. Soc, 1856) from stalks of currant at Albany, N. Y., lias 
been thought referable to it, and would be the oldest name ; but it doubtless belongs 
to A. ancylus, which Dr. Lintner has found on black currant in Albany. I do not 
recommend its use for ancylus, however, as it is an unrecognizable nomen seminudnm, 
so far as Fitch's publication goes. The names pyri and oslrea'formis, as applied to 
the Diaspis by Boisduval and Signoret, respectively, can have no claim, being merely 
misidentitications of Linnean and Curtisian species. We are thus obliged to fall back 
on Del Guercio's specific name, and call the insect Diaspis piricola (Del Guerc.); 
unless it can be proved identical with D. pyri Colvee, Ann. Soc. Ent. France, Bull., 
1881, p. lii. The difficulty with regard to Colvee's insect arises from his account of 
the grouped ventral glands; be gives, caudolaterals 18 to 20, cephalolaterals20 to 24, 
median wercr more than six, sometimes less or even none. In tho Diaspis the median 
group is larger, while the others are smaller, viz, median 8 to 12, caudolaterals 8 to 
14, cephalolaterals 12 to 13. 
