H. Kobayashi 
405 
and opens into the genital sinus, which connects the genital ducts with the 
external genital opening. The eggs are not numerous. The size is 0*035- 
0*037 mm. x 0*018 mm. and the shell is very thin. 
This species differs from Lepodora Odhner, 1905 1 , in certain characteristics, 
namely (1) that the genital opening lies directly anterior to the ventral sucker 
in the median plane; (2) that there is a relatively long genital sinus; and 
(3) that the receptaculum seminis is not present. In general structure, how¬ 
ever, it closely resembles Lepodora, but certainly it differs from Lepodora 
rachiaena. It seems to be a new species of the Genus Lepodora. 
(25) Phyllodistomum folium (Ofers.). 
I found the parasite in the bladder of Psevdobagrus auranticus collected 
in Lake Biwa and Kasumigaura. 
(26) Exorchis oviformis n.g., n. sp. (PI. XXVI, figs. 5 and 6). 
Exorchis n. 
Diagnosis. Very small. Body oval to spherical or even broader than long. 
Anteriorly tapers slightly, posterior end somewhat truncated. Cuticle spinose. 
Ventral sucker lies anterior to the middle of the body and is smaller than the 
oral. Alimentary canal consists of the short prepharynx, the pharynx, the 
short oesophagus and the intestinal caeca, which terminate near the posterior 
end. Excretory vesicle Y-shaped, arms extend to near the point of the intes¬ 
tinal bifurcation. Genital pore lies directly anterior to the ventral sucker. No 
cirrus-pouch. Testes lie symmetrically, exterior to the intestinal caeca, at the 
level of the middle of body; margin entire. Vesicula seminalis large, con¬ 
stricted in the middle. Ovary lies slightly posterior to the ventral sucker, 
nearly on the median line; smaller than the testis and weakly lobate. Broad 
Laurer’s canal present. No receptaculum seminis. Vitellaria in the anterior 
lateral region of body. Uterus with several loops in the posterior half of the 
body, partly extending outside the intestinal caeca. Eggs medium sized; 
shell thin. Habitat: in the intestine of fishes. 
Type species: E. oviformis n. sp. 
Exorchis oviformis n. sp. 
Diagnosis. Size 0*2-3 mm. x 0*2-0*28 mm. Shape often spherical. Oral 
sucker lies at the anterior end, 0*055-0*077 mm. in transverse diameter. 
Ventral sucker 0*04 mm. in diameter, situated at the level of the anterior 
third. Two eye-spots are present in the dorso-lateral region of the oral sucker. 
Other median pigment spots often present. Pharynx 0*03 mm. in breadth. 
Oesophagus 0*01-0*015 mm. in length. Intestinal caeca end near the posterior 
body end. Testes round or ellipsoid. Vesicula seminalis very large. Ovary 
with four or five lobes. Follicles of vitellaria relatively few in number. Laurer’s 
1 Odhner, T. (1905). Die Trematoden des arctischen Gebietes. Fauna Arctica. 
