Oxyspirura mansoni — Schwabe 
19 
lulu. The parasites were removed from the 
eyes of the birds by holding the head rigid 
and inserting the tips of a pair of dull- 
pointed forceps beneath the nictitating mem- 
brane. Worms thus obtained usually survived 
for at least 24 hours in physiological saline at 
room temperature. 
Young nymphs to be infected were first 
isolated without food or water in clean stack- 
ing dishes for at least 48 hours. Nymphs 
which were dead or enfeebled after this treat- 
ment were removed. Gravid female eye- 
worms were macerated in a drop of water to 
free the eggs from the vagina and uteri. The 
entire mass was then soaked up with a small 
bread crumb. The starved nymphs rapidly ate 
the moistened bread. It was later found that 
the nymphs would just as readily consume 
living female worms so this method of infec- 
tion was adopted. 
A roach to be examined was pinned, dorsal 
side downward, on a paraffin block. The head 
was severed with a sharp scalpel and the pos- 
terior abdominal segment was teased from the 
remainder of the abdomen with fine dissect- 
ing needles. The rectum remained attached to 
this segment and the entire alimentary tract 
was withdrawn in this manner. The alimen- 
tary tract and the remainder of the roach were 
each placed in a few drops of physiological 
saline solution on separate clean glass slides. 
Free third-stage larvae, if present, could, with 
the unaided eye, then be seen wandering 
about on the slide. Encysted second- and 
third-stage larvae were readily observed en- 
tangled in the Malpighian tubules or at- 
tached elsewhere along the alimentary canal, 
particularly in the region of the rectum. 
To observe the late first-stage larvae, the 
abdominal fat was dissected away from the 
body wall, placed in a drop of physiological 
saline solution, and examined beneath a cover 
slip with the aid of a compound microscope. 
In examinations for early first- stage larvae, 
the crop and esophagus were severed from 
the remainder of the alimentary canal, teased 
apart, and examined as a wet mount with a 
compound microscope. This procedure was 
repeated on separate slides for the midgut and 
hindgut. 
First-stage larvae were examined as live 
wet mounts or were stained vitally with 
methylene blue or fixed in Bouin’s solution. 
Second- and third-stage larvae were examined 
alive by compressing the cyst beneath a cover 
slip or by freeing the larvae from the cysts and 
fixing them in Bouin’s solution. Fourth-stage 
larvae were killed in Bouin’s solution and 
examined as wet mounts. 
When living larvae were too active for 
study they were anesthetized by a crystal of 
chloral hydrate introduced beneath the cover 
slip. 
The chickens used in these experiments 
were all hybrid stock (Rhode Island Red X 
New Hampshire Red) obtained at the age of 
2 weeks from the Department of Poultry Hus- 
bandry, University of Hawaii. They were 
housed on wire and fed commercial growing 
mash. 
Third-stage larvae were first obtained in the 
laboratory by the dissection of large numbers 
of infected roaches. Inasmuch as this con- 
sumed so much time and the larvae were not 
obtained in the numbers desired, a more satis- 
factory method was devised. It was observed 
that when infected roaches were torn apart 
and placed in physiological saline solution, 
heated to approximately 37° C., the larvae 
immediately began to migrate from the tis- 
sues of the roaches and to settle to the bottom 
of the container. This behavior of the larvae 
suggested the use of the Baermann apparatus, 
with which an ample supply of infective lar- 
vae was readily obtained. 
THE ADULT EYEWORM 
The sexually mature worms are found be- 
neath the nictitating membranes and in the 
conjunctival sacs and naso-lacrimal ducts of 
domestic chickens, ducks, and a number of 
other wild and domesticated birds. 
Anatomy of the adult eyeworm 
The adult Oxyspirura mansoni is a slender. 
