1887.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 367 



NOTES ON A TREMATODE FROM THE WHITE OF A NEWLY-LAID 



HEN'S EGG. 



By Dr. ED^VIIV 1.IIVTOIV. 



A Trematode, sent to me by the Smitlisoniau Institution for identiflca- 

 tiou, proves, upon examination, to be a specimen of Distomum ovatum 

 Eudolplii. 



The specimen was obtained and sent to the Smithsonian Institution 

 bv Mr. C. n. Shxyton, of Berlin, Wis. The ouly information furnished 

 with it is that the worm was found in the white of a freshlydaid hen's egg. 



The specimen was preserved in alcohol and was too opaque to show 

 any of the internal anatomy ; after placing it in glyceriue, however, so 

 much of the gross anatomy became visible as is shown in the appended 

 sketch. 



The intestine divides nearly midway between the two sucking-disks 

 into two branches, each of which continues as a slender, dark line witk 

 occasional darker-colored enlargements until it becomes indistinguish- 

 able amidst the opaque branches of the vitellaria. 



Two large yellowish opaque oval bodies lie side by side in the pos- 

 terior third of the body. These I take to be the testes, although they 

 seem disproportionately large for those organs. The yellowish-brown 

 vitellaria are quite conspicuous, and extend from a point nearly oppo- 

 site the posterior edge of the ventral sucking-disk along each margin of 

 the body to the posterior edge of the testes, their branches overlapping 

 the latter organs both dorsally and veutrally. The excretory duct of 

 the vitellaria shows plainly as a transverse dark line. It lies behind 

 the ventral disk at a distance from the latter ecpial to the diameter of 

 that organ. Immediately behind the disk it is transverse for an interval 

 equal to the diameter of the disk, then bends abrnptly forward, making 

 an acute angle at each side. From these angles the duct passes backward 

 and outward to each of the laterally placed vitellaria. The vitellarian 

 duct is much more plainly seen in a dorsal than in a ventral view. Close 

 behind the ventral disk, a little to the right of the central axis, is a lobed, 

 pear-shaped mass which I take to be the germarium, the anterior end of 

 which is larger and free, while the posterior end is the smaller and appears 

 to unite with the vitellarian duct. Adjoining the germarium on the right 

 is a small two-lobed glandular organ, or, more strictly, two glands lying 

 the one in front of the other — the posterior one larger and dorsal, the 

 anterior smaller and ventral. These are apparently the upper and lower 

 seminal vesicles. Behind these organs lies a larger, somewhat trans- 

 parent mass, irregular in outline and iudeliuite in extent, a part of which 

 doubtless represents the shell-gland. A darker part of this mass, which 

 lies to the left and behind the germarium, is probably the ovary. When 

 the specimen was rendered transparent with oil of cloves a cluster of 

 about a hundred ova was discovered lying near the ventral surface of 

 the body, immediately in front of the testes. Some scattered masses of 



