
550 RECORDS OF THE S.A. MUSEUM 
AMIDOSTOMUM CYGNI Wehr 193838. 
(Fig. 5.) 
A single male worm was taken from the black swan, Chenopis atrata. The 
extreme posterior end is apparently damaged but the characters of the spicules and 
of the anterior end indicate that the parasite belongs to the genus Amidostomum. 
The total length is 6-8 mm., and that of the oseophagus, :744 mm. The 
excretory pore is 171p from the anterior end. The buccal capsule is stout-walled, 
its internal diameter 21, and its depth 12; it contains three teeth, one larger 
than the other two. The spicules, each of which is complex and terminates in two 
unequal prongs, are 1538p long. The canoe-shaped gubernaculum is 72 long. 
The bursa is absent, presumably having been torn off at its base. 

Fig. 1. Capillaria gymnorhinae, egg. Fig. 2. Capillaria laricola, egg. Fig. 3. Capillaria 
plectroplites, egg. Fig. 4. Capillaria tandani, egg. Fig, 5. Amidostomum cygni, head. 
Fig. 6. Amidostomum biziwrae, head, Fig. 7-8. Ascarophis murrayensis: 7, anterior end; 
8, posterior end of male. Fig. 1-4, drawn to the same seale; fig. 5 and 6 to same scale. 
The specimen agrees with A. anseris (Zeder) R. and H. 1909, A. spatuluwm 
Baylis 1932, and A. cygnt Wehr in having three teeth. Its spicules and guber- 
naculum are much shorter than those of the first two of these species. The worm 
differs from A. anseris also in the size of the teeth relative to that of the buccal 
capsule, and from A. spatulum in the absence of any ‘‘epaulette’’ structures. 
Tt is arather shorter worm than A. cygmi, but the proportions of the various parts 
are similar. In the absence of a bursa it is impossible to verify the identification 
completely, but we suggest that our specimen belongs to A. cygnt. 
