THE CLOVER ROOT BORER 24 
these one contained an egg about one-fourth grown; the other, two 
immature eggs about one-eighth grown. Fifteen females, taken from 
roots in the field March 23, 1920, were almost without signs of egg 
development in the ovarian tubes. The single exception showed 
traces of first egg formation. Both sexes of the latter date had been 
feeding and evinced some development of the fat bodies. On March 
28,1916, of 6 females from roots collected in the field March 15 
and stored in a root cellar, none contained eggs, but 3 had been 
recently fertilized, as they contained balls of sperm in the accessory 
sacs. In one case, May 6, 1915, a female from a hibernation chamber 
in an old root had no egg development. 
Incipient egg formation, with rarely an egg as much as one-half 
srown, more frequently with eggs one-fourth grown, was usually 
found in females collected 
in flight. This state of 
the ovaries was the same 
in females swept late in 
the season of flight, ac- 
cording torecords for June 
3, 1916, and June 4, 1915. 
A careful examination 
of 14 females collected in 
flight April 26, 1920, cor- 
roborates the former 
statement and, in addi- 
tion, shows that only one 
of the 14 females was un- 
mated. All the others 
had mated previous to 
capture in flight, most of 
them so recently that the 
accessory sac was dis- 
tended with sperm and in 
at least one case so 
recently that no sperma- 
tozoa had yet reached the Fig. 12.—Diagrammatic drawing of sexual! organs of the female. 
spermatheca, a ] A bh oug h VY, ventral side; a, spermatheca; b, spermathecal gland; c, acces- 
2 = sory sac; d, vagina; e, ovarian tubes;f, paired oviducts; g, un 
the accessory : Sac Was paired oviduct; h, seminal duct; i, cementglands; j, anus. D, 
much swollen with sperm. aie enlarged. Redrawn from Rockwood. 
_. Examinations of the 
female genital organs during the oviposition period brought out 
the fact that eggs mature and are laid very slowly. Such exam- 
inations indicate that the ratio of developing eggs is approxi- 
mately 1: 44: 4: , etc. Examinations of females in egg galleries 
indicate a considerable interval of time between the maturation of 
the eggs, except in the rare case of simultaneous development 
in two ovarian tubes. The interval is apparently occupied by 
the female in feeding, prolonging the egg gallery, and forming the 
cell for the reception of the egg. Observations and dissections of 
females in egg galleries have also indicated that there is a consid- 
erably longer interval between maturation of individual eggs at 
the time an egg gallery is completed. In one case a female, which 
Was in a mine with five eggs, had no other eggs in her ovarian tubes 
more than one-eighth grown. Itseems likely that such interruptions 
