CONTRIBUTIONS TO AMERICAN HELMINTHOLOGY. 67 
genital apparatus, and I propose for its reception the generic name 
“Sphyranura,” with the following characters : 
Body depressed, somewhat elongate, expanded posteriorly into a 
caudal lamina, considerably wider than the body, bearing two im- 
mersed acetabula, two large hooks behind these, and sixteen small 
hooks (seven along each side of the lamina, and one in the centre of 
each acetabulum). Mouth ventral anterior, somewhat funnel-shaped, 
intestine with two branches anastomosing posteriorly. Excretory 
pore between the acetabula, two contractile bladders anteriorly. 
Oviparous. Parasitic on the gills and in the mouth of perenni- 
branchiate Amphibia. 
The specific characters in the allied genera are derived chiefly from 
the size, the caudal and genital armature, and the size and shape of 
the eggs. I accordingly note the following as characteristic of this 
species, which I propose to associate with the name of Dr. Osler as 
S. Osleri, n. sp. (Figs. 12, 13, 14.) 
Body 2.6 mm. in length by 0.7 mm. in breadth, narrowed at 
each end, especially where it joins the caudal lamina, which measures 
1 mm. across, and about 0.45 mm. in length. Large hooks 0.2 mm. 
long. Oviduct occupying the interval between the intestinal coeca, 
with numerous eggs; uterus with single mature egg, oval, with 
brownish-yellow shell, 0.364 mm. x 0.247 mm. 
I am not aware that any monogeneous Trematode, with the ex- 
ception of Polystomum integerrimum, has been hitherto found in 
any amphibian; and this seems to be restricted to the tailless forms. 
A careful examination of the gills, mouth-cavity, and urinary bladder 
of both perennibranchiate and caducibranchiate Urodela would pro- 
bably yield interesting results with regard to this family of Trema- 
todes. 
I regard the form under consideration as of great interest in view 
of the frequently asserted” relationship between Dactylogyrus and 
Gyrodactylus on the one hand, and Polystomum on the other, and I 
propose to recur to this after detailing the facts which I have been 
able to elucidate with the material at my disposal. 
26 Von Siebold, Untersuchungen iiber Gyrodactylus. Van Beneden, Animal Parasites, Eng 
Ed., p. 261. Willemoes-Suhm, Zeit. f. wiss. Zool. XXI. I have not seen this paper. The 
following is from Hofmann und Schwalbe’s Jahresberichte fur 1872, p. 274: ‘‘ Hat Zeller den 
Lebenslauf der Thiere vorziiglich aufgeklirt so gebiihrt Willemoes-Suhm die Prioritit der 
Publicirung der Beschreibung der Larve, sowie die Andeutung, dass die Aehnlichkeit derselben 
mit einem Gyrodactylus eine phylogenetische Entwickelung von Polystomum und Gyrodactylus 
aus einer Stammform wahrscheinlich mache.” 
