Tue Microscope. 147 
white larva or the pupa, the larger being empty and occupying 
the rest of the capsule (Fig. 2). They are sheaths developed 
about the insects’ eggs. From this hard case the mature gall-fly 
must gnaw its escape after forcing a passage through the parti- 
tion wall below, and creeping up the hollow stem. What instinct 
directs this little Cynips in the darkness of her prison so that she 
knows when she has ascended above the gall-tissue, and why 
does she never mistake the proper point where she must gnaw 
her escape? Does she creep up until lessening space forbids fur- 
ther progress and there bite the little round hole she always 
makes? Born in darkness and matured in a dungeon a hunch- 
backed gall-fly is wiser than the children of light. 
Her body is but one-tenth of an inch long, glossy and almost 
black, her wings expand perhaps one fifth of an inch from tip to 
tip; her mandibles, as might readily be inferred, are large and 
strong, and the end of her ovipositoris saw-toothed. Of her ge- 
nus there are said to be one hundred and fifty known species, 
and in a majority of them the males have never been seen. A 
German entomologist examined 15,000 specimens without find- 
ing a single male. He had 28,000 galls of another species, rear- 
ing 10,000 Cynips, all of whom were females. Osten Sacken alone 
claims to have seen a single male. 
It is not to the entire insect, however, that I wish to call spe- 
cial attention, but to a few points in her anatomy, and to the 
woody capsules within the gall. Without dissection of the abdo- 
men, and without the microscope, it would be difficult to imagine 
the origin of these spinous projections. 
,. The ovaries consist of many minute tubules collected into 
two sets, each cluster radiating from a centre. Within each tu- 
