BY ELEANOl! K. CUAt^E. 503 



The dursal median iirui-ess of the clingiug ijlug has nuuieruus tibres at its 

 base, and the bifid extremity is capable of being bent back on itself by the eon- 

 traction of the fibres contained within these lobes (PI. xxvi., fig. 3, m.d.p.). 



There is a strong layer of circular muscle in the parenchyma of the wall 

 surrounding the main ovoid mass of the plug, and it is continuous with the fibres, 

 which run into the septum dividing the cavity of the cup (PI. xxvi., fig's, 2, 4 cm.). 



Alimentary Canal. — Owing to the absence of a definite oral sucker as stated 

 above, the mouth leads directly into a pharynx 0.114: mm. long, 0.057 mm. 

 broad, with thickness of wall 0.019 mm. 



The intestine is dorsal in jjosition in fore part of the body, but (PI. xxvi., 

 fig. 4, int.) shows the two limbs crossing over in the septum to take up a ventral 

 position in the posterior cylindrical region (PI. xxvi., fig. 5, int.). 



Excretory System. — There is a ramifying system of excretory vessels, but with 

 the present imperfect specimens I am unable to give a detailed account of their 

 distribution . 



Reproductive System. — The reproductive system of H. repens is very similar 

 to the description given by Brandes (1891. p. 590, PI. xli., fig. 1) for //. variahile. 

 The genital organs are, however, confined to the posterior third of the animal. 

 The uterus, with the exception of its connection with the vesicula seminalis, has 

 the same relations as in H. variahile. In the latter the vesicula seminalis opens 

 into the uterus at the base of the genital papilla, whereas in H. repens it- joins 

 the female duct near the extremity of the papilla (PI. xx\'i., fig. 1). 



The eggs are large, 0.095 x 0.07(5 mm.; 0.133 X 0.095 mm. 



There are numerous vitelline glands, which extend into the anterior region, 

 and are found in the two swollen masses of the dorsal wall of the plug (PL xxvi., 

 fig. 2, v.g.). In the region of the reproductive organs, the follicles are confined 

 to a ventral position, but they do occur dorsally both in front of and behind these 

 organs. 



Affinitie.^:. — //. variahile Xitzsch, according to Brandes (1891. p. 590, PI. xli.. 

 fig. 1), is closely allied to H. repens in the general arrangement of the organs, but 

 in shape U. repens is considerably more elongated, and the plug occupies a much 

 greater proportion of the body. Holostomum simplex Johnston (1904, p. 112, 

 PI. vii., figs. 1-3), from the same host, has somewhat the same fonn, but the 

 clinging plug is of a simpler tyiie. In no other species described have I found 

 the absence ol oral sucker noted. 



Host. — Fi'om the intestine of Xotophoyx twvae-hnllandiae, collected at Terri- 

 gal, N.S.W. 



Type Ko. Vr.544 in the Australian iluseum, Sydney. 



References. 



Braxdes. 1888. Uber das Genus lldlostdinHni Xitzsch. Zool. Anz., xi., pp. 



424-426. 

 1891. Die familie der Holostomiden . Zool. Jahrh., v., pp. 549-G04, 



PI. xxxix.-xli. 

 "DujAEDlx. 1845. Histoire naturelle des Helminthes ou vers intestinaux. Paris. 

 Johnston. 1904. On some species of Holostomidae from Australian Birds. 



Proc. Linn. Soe. N.S. Wales., xxix., pp. 108-116, PL v.-vii. 

 LiNTOX. 1892. Notes on Avian Entozoa. Proc. U.S. Nat. Mm., xv., pp. 87-113. 



PL iv.-viii. 



