Archive image from page 284 of Discovery reports (1932) Discovery reports discoveryreports04inst Year: 1932 ENCHYTRAEIDAE 263 development of the male cells, and the compact, ovoid, and encapsuled penial body with characteristic structure are absent, and are represented by the less specialized con- ditions found in Enchytraeus. The specific name is taken from the Greek koXttlt-i], dwelling on a bay (/coXttos). Genus Michaelsena, Ude Michaelsena monochaeta (Michaelsen) (Fig. 14). Enchytraeus monochaetus, Michaelsen, 1888, p. 66, fig. 6 a-c. St. 159. 21. i. 27. 53° 52' 30' S, 36° 08' 00' W; dep
Archive image from page 284 of Discovery reports (1932) Discovery reports discoveryreports04inst Year: 1932 ENCHYTRAEIDAE 263 development of the male cells, and the compact, ovoid, and encapsuled penial body with characteristic structure are absent, and are represented by the less specialized con- ditions found in Enchytraeus. The specific name is taken from the Greek koXttlt-i], dwelling on a bay (/coXttos). Genus Michaelsena, Ude Michaelsena monochaeta (Michaelsen) (Fig. 14). Enchytraeus monochaetus, Michaelsen, 1888, p. 66, fig. 6 a-c. St. 159. 21. i. 27. 53° 52' 30' S, 36° 08' 00' W; depth of net 160 m. Net DLH (large dredge, heavy pattern). About a dozen small worms or fragments of worms, mostly bent or twisted. The species was described by Michaelsen as long ago as 1888 from specimens taken in South Georgia. Identification is easy, by means of the setae. These conform entirely to Michaelsen's description—a single seta only per bundle, the ventral setae beginning in segment v, the lateral in xvii or there- abouts ; I find a slight distal curve in some (lumbricilline setae). The spermathecae (Fig. 14) show a broadly pear-shaped ampulla with patent communication, somewhat drawn out, with the oeso- phagus ; the duct is sharply separate, as long as the ampulla. Owing to the internal degeneration in the genital segments and the generally unfavourable condition of the worms, I am unable to describe completely the penial body, concerning which Michaelsen has not given us any information. The vas deferens appears to pass backwards in numerous windings for several segments, I think as far as segment xiv; the penial body seems to have possessed a muscular capsule, and not to have consisted of discrete masses of gland cells after the manner of E. albidus. The locality of the specimens deserves a word of note; they were dredged from 160 m.—a very unusual depth for Oligo- chaetes, which are usually confined to the shore and seldom stray out to sea. Michaelsen's spec
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