. Enchytræidæ of the west coast of North America. Enchytraeidae; Annelida. 56 EISEN Locality.— Found at Goose Lake, Alturas and other localities in Modoc County, California. Collected by Dr. Richard C. McGregor. Probably common in the mud of creeks and lakes in the Sierra Nevada region of northern California. Characteristics.— Readily distinguished exteriorly by very large copulatoiy papillae in XII, especially in specimens where they are fully extended, the papillae then being as long as the diameter of the body. Interiorly it is prominently characterized by the enormously large accessory gla
. Enchytræidæ of the west coast of North America. Enchytraeidae; Annelida. 56 EISEN Locality.— Found at Goose Lake, Alturas and other localities in Modoc County, California. Collected by Dr. Richard C. McGregor. Probably common in the mud of creeks and lakes in the Sierra Nevada region of northern California. Characteristics.— Readily distinguished exteriorly by very large copulatoiy papillae in XII, especially in specimens where they are fully extended, the papillae then being as long as the diameter of the body. Interiorly it is prominently characterized by the enormously large accessory glands, which open in the immediate vicinity of the sperm- ducts (p1. IX, fig. 5). DETAILED DESCRIPTION. Setce. — In the first few somites the number of setse varies between three and four in the lateral fascicles, while in the ventral fascicles we find six setse in the three anterior fascicles and five in the following. Posterior to cli- tellum the seta in the ventral rows are unif o r m 1 y five, while in the lateral rows they are only four. All the setae in the same fascicle are of about the same size. Head-pore.— This pore is situ- ated (fig. 29, a) a little in front of the shallow groove which separates prostomium from somite I. Spermiducal apparattis (p1. ix, figs. 4 and 5).—As stated, the large sexual papilla is most conspicuous. When fully extended its long diameter is equal to the diameter of the body at somite XII (p1. IX, fig. 5). The sperm-ducts open at the apex, and this latter is surrounded by the elevated margin of the body-wall, here consisting of large broad cells. Surrounding the opening of the sperm-ducts is a small bulb, into which opens a ring of very large accessory glands. These glands extend inward to the center of the body-cavity. Their structure seems to resemble that of the septal glands. The sperm-. FiG. 30. MeseiicJiytrcEUS Please note that these images are extracted from scanned page images that may have been digitally enhanced f
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