. Enchytræidæ of the west coast of North America. Enchytraeidae; Annelida. ENCHYTR^ID^ 93 MARIONINA AMERICANA sp. nov. p1. XIV, fig. I ; text-figs. 6i and 62. Definition. — Length 10 mm., width .5 mm. Somites about 50. Prostomium blunt, Sette : ventrals, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, o, 2, 4, 4, 4, etc.; laterals, 2, 2, 2, 2, 3, 2, etc. Head-pore immediately in front of the groove between prostomium and somite I. Clitellum small, XII and XIII. Sexual papillae small, cylindrical, truncate. Brain posteriorly slightly emar- ginate; posteriorly much broader than anteriorly. Dorsal vessel rises pos


. Enchytræidæ of the west coast of North America. Enchytraeidae; Annelida. ENCHYTR^ID^ 93 MARIONINA AMERICANA sp. nov. p1. XIV, fig. I ; text-figs. 6i and 62. Definition. — Length 10 mm., width .5 mm. Somites about 50. Prostomium blunt, Sette : ventrals, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, o, 2, 4, 4, 4, etc.; laterals, 2, 2, 2, 2, 3, 2, etc. Head-pore immediately in front of the groove between prostomium and somite I. Clitellum small, XII and XIII. Sexual papillae small, cylindrical, truncate. Brain posteriorly slightly emar- ginate; posteriorly much broader than anteriorly. Dorsal vessel rises posterior to clitellum. In- testine with few and thin chlo- ragogen cells. Spermathecae consist of a narrow and com- paratively long duct, and a short and wide ampulla furnished with two short diverticles; the am- pulla does not seem to connect with the intestine. The penial bulb contains two kinds of gland- ular cells, one kind being more granular and staining more deeply than the other. Sperm- duct narrow and coiled, confined to XII and XI. Testes entire, but covered by a cap-like sperm-sac confined within XI. No ovisac. No ventral glands. Lymphocytes large, round- \:;;-^z y^ ed, disk-like. Color pale, without pig- ment. Locality.—Port Clarence, Alaska, Dr. Anton Stuxberg, Vega Expedition (July 23 to 27, 1S79). A single specimen. Characteristics.—The single specimen being in a poor state of preservation pre- vented any detailed investigation. The anterior part of the worm was sectioned transversely. The nephridia are not in a sufficient state of preservation to allow their finer struc- ture to be satisfactorily studied. The spermatheca is distinctly char- acteristic of the species. Setce. — The setae of the ventral fascicles diminish in size toward the ventral interval, while those of the lateral fascicles diminish toward. Marionina Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - c


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Keywords: ., bookauthorharrimanalaskaexpedit, bookcentury1900, bookdecade1900