1881 .] 
173 
position of it in tlic two forms, offering primti facie evidence that there 
are two species, and not merely different stages of development in one 
species as has been stated. (1). In one type the upper surface is 
smooth, almost flat within the border (which also is regular, compact, 
and smooth), and destitute of imbrication, the segments being dis- 
tinctly visible from side to side, only divided in the middle by a 
continuous, longitudinal, impressed line. (2). In the other type the 
border is less regular and more flaky, especially in the adult, and the 
whole dorsal surface is covered with protuberant, overlapping, scale- 
like or flaky lamella) in two longitudinal rows or ridges, whereby the 
segmentation of the body is quite hidden. 
(1.) In the first type there are, in the adult ? , other specialities : 
— the broad, short-oval form, the pale cream-white colour, the tes- 
taceous colour of the legs and antennae, the tarsus as long as the tibia ; 
the antennae short, stout throughout ; the broad caudal lamination 
projecting beyond the border to a comparatively short extent, its ex- 
tremity broadly rounded, its surface longitudinally crenate (not 
lamellate). This caudal projection arises below the circumferential 
border of the body, which remains entire : it forms the covering part 
of the marsupium , which contains at first the eggs, and then the young 
larvae. (The same kind of structure, but of larger dimensions, exists 
in O. urticcB .) To this type belong, as one distinct species (O. 
cataphracta ) , — 
¥ . Coccus cataphr actus, Shaw, Nat. Misc., v, pi. 182 (1791), Glen. Zool., vi, 194, pi. 
62 (1806). 
¥ . Dorthesia cataphracta, West., Intr. Mod. Class. Ins., ii, 443, fig. 118, 20 (1840). 
¥ . Dorthesia chiton , Zett., Ins. Lap., 314 (1840). 
$ . Orthezia urticce, Sign. syn. partim, Essai sur les Cocliinolles, 423 (1875). 
$ . Orthezia Signoreti, F. B. White, Scot. Nat., iv, 160, pi. 2, fig. 1, antennae (1877). 
In the Scotch examples, for which I am indebted to Dr. F. 
Buchanan White, there is, on the middle line of each of three anterior 
(thoracic) segments, a very small scutelloid process or appendage : 
these are represented in Shaw’s figure, but are exaggerated. 
The adult $ has not been observed, but Dr. Buchanan White says 
(l. c.) : “ I have only seen one larva, and that not in good condition, 
but, as far as I could judge, the antenna) resemble in structure that of 
the larva of urticce." 
The species appears to have been found only in northern regions 
— Lapland, Greenland, Norway, Scotland, Ireland, and the north of 
England. 
(2.) In the second type, in the adult $ , the other characters to 
be noted are: — the long-oval form; snow-white colour ; the piceous 
