Oxyspirura mansoni — SCHWABE 
23 
the posterior half of the body. It is surround- 
ed by a cuticular ring of highly refractile ma- 
terial. The vagina extends anteriorly from the 
vulva and is divisible into two parts, by rea- 
son of the thickness of the wall. The proxi- 
mal portion is nearly 150 in length and 35 ju 
in diameter. The distal thicker- walled portion 
is approximately 60 fx in diameter. The vagina 
branches to form the two thin- walled uteri. 
These extend forward to the posterior region 
of the esophagus, where they reflex and ex- 
tend back to the region of the vulva. The 
diameter of the uteri decreases to 22-30 /x to 
form the two ovaries which lie as a coiled 
mass in the posterior portion of the body 
cavity. 
HOSTS OF THE EYEWORM 
Nematodes inhabiting the eyes of birds 
have been reported from a number of species. 
Most of these parasites are members of the 
genera Thelazia and Ceratospira, or are species 
of the genus Oxyspirura other than 0. mansoni. 
The hosts of only those eyeworms which 
have been definitely identified as Oxyspirura 
mansoni (or parvovum) are recorded here. 
Definitive hosts 
Manson’s eyeworm has been reported to 
occur naturally in the following birds: do- 
mestic chicken {Callus domesticus) (Cobbold, 
1880); turkey {Meleagris gallopava) (Cram, 
1927); peafowl {Favo cristatus) (Magalhaes, 
1888); English sparrow {Passer domesticus) 
(Illingworth, 1931; Alicata, 1947); mynah 
bird {Acridotheris tristis) (Alicata, 1947); 
Chinese dove {Streptopelia chinensis) (Alicata, 
1947; Schwartz and Schwartz, 1949); Japanese 
quail {Coturnix coturnix japonica) (Schwartz 
and Schwartz, 1949); pheasant {Phasianus 
torquatus torquatus and P. vesicolor vesicolor) 
(Schwartz and Schwartz, 1949). 
Through the cooperation of Paul Breese, 
Director, the birds in the Honolulu Zoo are 
being examined for the presence of Oxyspirura 
mansoni. This survey is not complete as yet, 
but the following new hosts may be recorded: 
the great Argus pheasant (Argusianus argus 
argus) and the Siamese fireback pheasant 
{Diardigallus diardi) . 
Role ofi the natural reservoir hosts imthe spread of 
the parasite in Hawaii 
During the course of this investigation 
mynah birds, English sparrows, and Chinese 
doves have been trapped on the University 
campus and have been found to harbor Man- 
son’s eyeworm. Similar observations have 
been made by other investigators in other 
parts of Hawaii (Illingworth, 1931; Alicata, 
1947; Schwartz and Schwartz, 1949; Tanada, 
personal communication) . 
TABLE 3 
Numbers of infective Larvae per Roach 
(100 Surinam Roaches Examined at Each Locality) 
STAGE 
RANGE 
MIYATA POULTRY 
FARM, WAIALAE, 
OAHU 
UNIVERSITY FARM, 
MANOA VALLEY, 
OAHU* 
WAIKIKI, OAHUf 
Max. 
36 
3 
Adult roaches 
Min. 
16 
0 
None 
Ave. 
23 
Max. 
34 
2 
Nymphs 
Min. 
1 
0 
None 
(Final instar) 
Ave. 
3 
Max. 
6 
0 
Young nymphs 
Min. 
0 
0 
None 
*Roach population low (daily removal of manure, weekly chlordan spray). 
fApproximately 4 miles from nearest poultry farm. 
