858 [Assembly 
resemblance to that of Uropoda vegetans (PI. 34, fig. 6), a species 
which is quite common upon several of our American beetles. 
The Ant-tick measures from 0.010 to 0.015. It is of a cherry red color,younger 
individuals being translucent and pale reddish; it is shining, with translucent legs 
clothed with short hairs. It is of a circular form, very slightly longer than wide, 
flattened, and commonly presents a translucent margin. The legs are shortish, taper 
gradually, and the feet are not half the thickness of the shanks. The anterior legs 
have not the slendertect of the three other pairs, but are antennoe-like, and have at 
their tips several short coarsish hairs and a single bristle slightly longer than theso 
hairs. The palpi or feelers rarely project beyond the anterior margin, and their tips 
arc also clothed with short hairs. 
This ant appears to be a distinct species from those which have 
been heretofore described, and I therefore propose for it a name 
in allusion to the situation in which it occurs. It may be distin¬ 
guished by the segments of its abdomen being glabrous and 
polished at their bases and minutely punctured on their posterior 
half, with two transverse rows of fine erect bristles, one in the mid¬ 
dle the other at the tip of each segment. The Silky ant (Formica 
subsericea) described by Mr. Say in the Boston Journal of Natural 
History (vol. i. p. 289), is closely related to this Species, but is 
destitute of punctures on the abdominal segments. 
The males of this species measure 0.30 to the tip of the abdomen which is about 
0.08 in diameter, 0.32 to the t.ip of the closed wings, and the wings spread 0.45. They 
arc black and shining. The head is nearly globular, and there are, as usual in this sex, 
three distinct ocelli or little eyes upon the crown, and from the anterior one of these 
a fine impressed line runs forward to the face. The fiicc is rough and unequal, with 
impressed punctures, from each of which arises a short hair. The tips of the jaws 
are tinged with brown; the upper lip is blackish-brown or sometimes cinnamon-yel¬ 
low; the feelers are long slender and thread-like, and clothed with fine short hairs; 
the antennae are long and slender, of equal thickness, their tips with an ash-gray re¬ 
flection. The thorax is slightly broader than the head, oval, smooth, and without 
punctures or hairs. The abdomen is somewhat wider than the thorax, and composed 
of seven segments, of which the basal one is contracted as usual, forming a slender 
pedicel, with an erect hump or scale on the middle of its upper side, which, viewed 
laterally, is of a wedge-shaped form, short and thick, and bears a few short hairs; 
its summit is cut off transversely and is distinctly notched in its middle. The re¬ 
maining segments form a regular oval mass, rounded at base and pointed at tip. The 
basal third or half of each segment is glabrous and shining, the remainder is minutely 
punctulated and clothed with fine short hairs, scarcely perceptible, whilst on each 
segment are two transverse rows of fine bristles which are sometimes interrupted 
along the middle of the back, one row on the posterior margin, the other near the 
middle, these bristles arising from rows of equidistant punctures. At the tip 
