PARASITE-S OF THE JOINT-WORM. 
557 
the bottom' of the shank and the contiguous part of the 
foot; The length of the' body is ten hundredths of an 
inch, being somewhat less than that of the Eiirytoma. 
‘ From my samples of the straw I have obtained another 
and a different parasite, belonging to the same family, but 
to the genus Torymus. The specimen is a female, and, 
like others of the same genus, it is provided Avith an ex- 
serted slender piercer, nearly as long as its own body. 
The latter is about as Ions; as that of the Pteromalus above 
described, and is of a deep black color, slightly tinged 
with green on the face and thorax, both of w^hich are 
rough and opaque, Avhile the hind body is smooth and pol¬ 
ished. The fore Avings haA^e an elongated cloudy spot 
near the middle, and the oblique branch is very short. 
The thighs, claAvs, and the antennae except the basal joint, 
are blackish, the other parts of the legs and the base of 
the antennae are pale yellow. The hindmost thighs are 
much thicker than the others, and are notched beneath the 
end. The eyes have a dull reddish tinge, perhaps not 
their true color in life. Professor Cabell has sent to me 
some specimens of this Torymus^ including a male, AA^hich 
differs from the female in haAung all the joints of the an¬ 
tennae black. 
' The raA^ages of the joint-Avorm in the Avheat-fields of 
Virginia are said to haA^e been first obserA^ed in Albemarle 
County, about four or five years ago. They have alarmingly 
increased from year to year, and liaA^e extended over many 
parts of the adjacent counties, becoming more aggravated 
each time that they are reneAved in the same place. The 
loss occasioned thereby often amounts to one third of the 
average crop, and is sometimes much greater; and during 
the present season, “ some farmers did not reap as much 
as they sowed.” These statements are made chiefly on 
the authority of Professor J. L. Cabell, of the UniversitA^ 
of Vir ginia, AAdio has giA^en some attention to the natural 
history of the joint-Avorm, and has recently communicated 
