13 
aud forms a very excellent protection (PL I, Fig'. 5, d)." When fresh 
the mass is soft aud moist, but it soon acquires a firm consistency. 
Daring the operation the female is very inteut on her work, aud may 
be gently approached without becoming alarmed, though when sud- 
denly disturbed she makes great efforts to get away, and extricates 
her abdomen in the coarse of a few seconds, the time depending on the 
depth reached. 
The legs are almost always hoisted straight above the back during 
the process, as shown in the figure (Fig. 1), with the shanks hugging 
more or less closely the thighs. Sometimes, however, especially when 
the abdomen is fully buried, the ends of the hind feet may rest firmly 
on the ground, as has been observed by Dr. Packard in the case of 
femur -rubrum. 
The time required for drilling the hole and completing the pod will 
vary according to the season and the temperature. Dariug the latter 
part of October or early in November, 1876, when there was frost at 
night and the insects did not rouse from their chilled inactivity until 9 
o'clock a. in., the females scarce had time to complete the process dur- 
ing the 4 or 5 warmer hoars of the day ; but with higher temperature 
not more than from 2 to 3 hours would be required. 
We have been for weeks with the insects where they were so thickly 
ovipositing that the light, clay-yellow ground would be darkened by 
them, and have laid on a closely-grazed sward for hours with speci- 
mens in the act all around, and have repeatedly verified all that we 
have here described. 
Philosophy of the Egg-mass.— To the casual observer the eggs of this 
locust appear to be thrust indiscriminately into the hole made for their 
reception. A more careful study of the egg-mass, or egg-pod, will 
show, however, that the female took great pains to arrange them, not 
only so as to economize as much space as possible, consistent with the 
form of each egg, but so as to best facilitate the escape of the young 
locust $ for if, from whatever cause, the upper eggs should fail to hatch, 
or should hatch later than the lower ones, the former would offer an 
impediment to the exit of the young in their endeavors to escape from 
these last, were there no provision against such a possibility. The eggs 
are, indeed, most carefully placed side by side in four rows, each row 
generally containing seven. They oblique a little crosswise of the cyl- 
inder (PL I, Fig 4, a). The posterior or narrow end, which issues first 
from the oviduct, is thickened, and generally shows two pale rings 
around the darker tip (PL I, Fig 5, o). This is pushed close against the 
bottom of the burrow, which, being cylindrical, does not permit the outer 
or two side rows to be pushed quite so far down as the two inner rows, 
and for the very same reason the upper or head ends of the outer rows 
are necessarily bent to the same extent over the inner rows, the eggs 
when laid being somewhat soft aud plastic. There is, consequently, an 
irregular channel along the top of the mass (PL I, Fig. 5, c), which is 
