ON THE TREMATODE PARASITES (GENUS <i>PHILOPHTHALMUS</i>) FOUND IN THE EYES OF FORMOSAN DOMESTIC BIRDS

Abstract

I have found two species which belong to the genus Philophthalmus in the nictitating membrane of Formosan domestic birds (duck and chicken).The species from chicken closely resembles Philophthalmus gralli MATHS and LEGFR (1910). I think that my species will be the same as Philophthalmus gralli.In some degree the species from duck resembles Philophthalmus gralli and Philophthalmus palpebrarum LOOSS (1899), but it will be found that my species differs from these species in many respects. I think that my species will be new and I give it the name Philophthalmus anatinus n. sp.Philophthalmus anatinus n. sp. (Fig. 1-4)Diagnosis. The worm light yellowish in the fresh condition, lancet-shaped, small sized, about 3.57 to 6.5mm. in length and 0.84 to 1.05mm. in maximum width which lies at the anterior part of the posterior third of the body, from which point the body gradually narrows anteriorly to a broadly rounded end.The cuticle somewhat thick aud the spines absent.The suckers well developed. The oral sucker, situated a little ventrally in the anterior end and somewhat traverse-elliptical, and about 0.39 to 0.51mm. by 0.36 to 0.37mm. in diameter. The ventral sucker, situated a little behind the anterior intestinal archin the part of anterior quarter and about 0.47 to 0.54mm. in diameter.The well developed pharynx spherical in shape, with diameters of 0.29 to 0.34mm. by 0.27 to 0.49mm. The oesophagus short, rather expansive. The intestinal caeca extends posteriorly.On the median line, more or less behind the commencement of the posterior third of the body, the two testes arranged on a straight line, and the testes are large, globular in shape, but owing to pressure of the testes the posterior margin of anterior testis and the anterior margin of posterior testis somewhat flat, the anterior testis measuring 0.3 to 0.5mm. by 0.22 to 0.47mm. and the posterior testis 0.3 to 0.4mm. by 0.25 to 0.45mm. The cirrus pouch is long and extending posteriorly far behind the ventral sucker. The seminal vesicle occupies the posterior third of the pouch and continues anteriorly into a prostate region. This terminal duct opens into the cnmparatively long genital atrium, the exterior aperture of which lies on the median line at the level of the intestinal bifurcaiion. The cirrus long, measuring 1.2mm. in length and lies in the cirrus pouch while living.The ovary generally spherical in shape, measuring 0.22mm. by 0.22mm. in diameter, situated on the median line and before the anterior testis. In my specimen, it is difficult to find out the position of the ovary, being covered by the uterus convolutions filled with immature eggs. Laurer's canal is short and opens on the median line of the dorsal face. I cannot determine the existence of the receptaculum seminis, but here is an expansive region filled with spermatozoids. Perhaps, it will be replacement of the receptaculum seminis.The york glands tubiform, light chocolate in colour, and the anterior half situated on the external side of the intestine, and extends anteriorly to the level of the posterior margin of the cirrus pouch, and posteriorly to the level of the anterior testis. The paired york ducts lie in the region of the anterior testis, and uniting at the antero-dorsal margin of the anterior testis.The uterine loops fill up the space between the ventral sucker and the testis. The part of the uterus convolution near the ovary extending to right and left, going beyond the intestine, and arriving to both side of the body. A party turns posteriorly on the outside of the anterior testis and another proceeds forward until the cirrus pouch and then ending to the vagina. The long vagina proceeds forward, parallel to the cirrus pouch, opening into the genital pore.The mature eggs are elliptical, with a thin shell, about 0, 109 to 0.117mm. long and 0.058 to 0.062mm. wide, both sides being asymmetrical.