278 
Cladorchis subtriquetrus Bud. 
anatomy emphasis is laid on certain individual features which have 
not been generally recognized although they have been pointed out 
by some writers. These features are: the pre-oesophageal sphincter, 
oesophageal musculature and heavy ventral subcuticular musculature. 
From the point of view of development the minor branching of the 
testes has been noted by other authors and it has been assumed that 
the testes become more complex with maturity. Previous writers 
make no reference to vitelline development. That this development 
occurs at a late stage is best shown by reference to my second specimen 
(Fig. 2) wherein but a few follicles are noted; the late development- 
may explain why the ducts could not be traced in my material. 
The absence of any inflammatory changes near the fluke, and the 
good nutritional condition of the host indicate that the worm is a 
commensal parasite, this impression being strengthened by observance 
of vegetable fibres in its caeca. 
REFERENCES. 
1814: Amphist. subtriquetrum. Rudolphi, Mag. f. d. n. Entdeck. in. d. ges. Naturk. 
Berl. (Apr.-Juni 1812), v. 6, 2. Quartal, pp. 83-113 in Castor fiber, Berlin, May. 
1897: Amphist. subtriquetrum. Otto, Deutsche Ztschr. f. Thiermed. u. vergl. Path., 
xxn. p. 105. 
1901: Cladorchis (Stichorchis ) subtriqxie.trus. Fisckoeder, Zool. Anz., Leipz. v. 24, 
24 June 1901, p. 373. 
1903: Cladorchis (Stichorchis) subtriquetrus. Fischoeder, Zool. Jahrb., Jena, Abt. 
f. Syst., v. 17 (4-6), 9 Feb., p. 494. 
1910: Cladorchis. Stiles and Goldberger, Hygienic Laboratory Bulletin, No. 60, 
Washington, D.C. 
1914: Amphistomum subtriquetrum. Duff, Trans. Royal Soc. of Canada, Sept. 1914, 
Series III. Vol. vm. p. 87. 
For full bibliography see Index Catalogue of Medical and Veterinary Zoology, 
Washington, D.C. Bulletin, No. 37, 1908, p. 96. 
DESCRIPTION OF PLATE V. 
Fig. 1. Longitudinal section through immature, artificially flattened specimen (no. 2). 
sph. oral sphincter; o.s. oral sucker; oe. oesophagus; ca. caeca; ov. ovary; a.t. anterior 
testis; p.t. posterior testis; v.d. vas deferens; ut. uterus; ac. acetabulum. The testes 
are sectioned through their dorsal halves. Note their lack of branching in this 
immature specimen. 
Fig. 2. Transverse section at junction of second and third body fifths through posterior 
testis, t.bod. body of testis; t.br. testicular branches; ca. caeca; ut. uterus; vit. 
vitelline follicles. Compare robustness of ventral and dorsal cuticular muscles. 
