NO. 2040. NOTES ON A VIVIPAROUS DI8T0ME— LINTON. 555 



The length of ova in tho posterior folds of the uterus varied from 

 0.066 to 0.079; the breadth of each one measured was 0.040. The 

 length of ova in the anterior folds of the uterus varied from 0.082 to 

 to 0.10 and the breadth from 0.046 to 0.060. Length of a miracidium 

 0.08, breadth 0.05. Length of a redia 0.06, breadth 0.03. 



Type-specimen. — Cat. No. 7377, Helminthological Collections, 

 U.S.N.M. 



REFERENCES. 



1902. Fascioliden der Vogel. Braun, Zool. Jahrb., vol. 16. p. 146, fig. 89. 



1906. Some New and Little-known Trematodes. Nicoll, Ann. Mag. Nat. Hist., eer. 

 7, vol. 17, p. 519, pi. 12, figs. 4 and 5; pi. 13, figs. 6 and 7. 



1907. Parorchis, n. nom., ior Zeugorchis. Nicoll, 1906. Nicoll, Ann. Mag. Nat. Hist., 

 ser. 7, vol. 19, p. 128. 



1907. Parorchis acanthus, the type of a new genus of trematodes. Nicoll, Quart. 

 Joum. Micr. Sci., vol. 51, pp. 34.5-355, pi. 21, figs. 1-6. 



EXPLANATION OF PLATE 43. 



a. oral sucker. ph. pharynx. 



ex. excretory pore. pr. prostate. 



g. genital pore. sv. seminal vesicle. 



t. intestine. t. testis. 



7n. metraterm. u. uterus. 



n. nerve. v. ventral sucker. 



o. ovary. vd. vas deferens. 



oe. esophagus. vg. vitellaria. 



Fig. 1. Three specimens lying in sea water, ventral view. 



2. Outlines of four mounted specimens. 



3. Ventral view of specimen mounted in balsam. Length 3.75 mm. 



4. Dorsal view of anterior portion of another specimen. Diameter of head 0.7 



mm. 



5. Ventral view of anterior end of specimen, optical section; n. nerve. 



Breadth of head 0.7 mm. 



6. Spines of neck, surface view, life; length 0.022 mm. 



7. Same, marginal view. 



8. Yolk-forming cells, along margins of neck and body, life. 



9. Egg shell with transverse fissure at larger end from which the miracidium has 



10. Egg containing a ciliated lai"va, life. 

 '11. Ciliated larva with single redia, liberated from egg. 



12. Ciliated cell from crushed miracidium, life. 



13. Pigment spots of miracidia, sketched from living specimens. 



14. Redia removed from miracidium, life; length 0.14, breadth 0.04; length of 



pharynx 0.017, breadth 0.020 mm. 



15. Miracidium with contained redia just escaped from egg; sketched from 



mounted specimen. 



16. 17, 18. Miracidia with redise from specimens mounted in balsam. 



