New York AGRICULTURAL EXPERIMENT STATION. 161 
DESCRIPTION AND LIFE HISTORY.?? 
Egg— Ovum elliptical; chorion translucent, smooth, shining. 
Longest diameter 204 microns, greatest width 85 microns. 
Adult-—(Female.) Body elongate, sides nearly parallel, ante- 
rior portion narrowing to head, posterior margin truncate; lateral 
angles rounded. Length, 240 microns, width 70 microns. 
The body is composed of a cephalo-thorax and abdomen. On 
the anterior margin of the cephalo-thorax is the rostrum with large, 
toothed, sickle-shaped mandibles. The rostrum is set in a wide col- 
lar which is attached to the body. There are several small hairs 
near the base of the mandibles. 
The cephalo-thorax is somewhat triangular, broadest at the pos- 
terior margin, with angles rounded and sides incurved. Legs I 
and II are borne on this division and between them is a clavate 
body. On the dorsum there are three pairs of long hairs; the front 
pair smallest, about 12 microns in length; the middle pair about 
20 microns in length and situated closer to the lateral margin than 
the third pair. The third pair are almost in the center of the 
cephalo-thorax and directly beneath pair I; they extend nearly to 
the end of the abdomen. ‘The clavate organ is broadly rounded. 
The abdomen is separated from the cephalo-thorax by a trans- 
verse constriction. Caudad of this are several telescoping portions 
ot the integument which give the abdomen a segmented appearance. 
On the dorsum about 12 microns behind the transverse constric- 
tion and near to the lateral margin is-a pair of strong hairs about 
33 microns in length; just below these and 15 microns from the 
median.is a stout pair 17 microns long; three other pairs of dorsal 
hairs are situated just below the caudal margin of the telescopic in- 
tegument, the last pair being the shortest. A single pair 75 microns 
long is borne near the end of the ventral section and is the longest 
pair on the abdomen. On the caudal margin near the median are 
three pairs of very small hairs, the longest being 10 microns in 
length. 
*“ While the external anatomy of the mature mites bred on carnations cor- 
responds with the descriptions and figures of the adults of P. graminum, 
our studies on the early life history of the species do not agree in some 
particulars with Reuter’s account. This difference may perhaps be ex- 
plained by his recent investigations on the embryonic development of this 
mite. 
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