. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 262 DISCOVERY REPORTS with a small everted rim at the mouth. In one specimen a rudimentary third funnel was seen, as a small bud on the side of one of the larger ones. I do not remember noticing this particular abnormality before. The vas deferens, 20/x in diameter, forms a close coil on each side, which may extend into the hinder half of the segment amongst the large ova. The penial body is of the enchytraeine rather than of the lumbricilline type. It con- sists of a number of pear-shaped masse
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 262 DISCOVERY REPORTS with a small everted rim at the mouth. In one specimen a rudimentary third funnel was seen, as a small bud on the side of one of the larger ones. I do not remember noticing this particular abnormality before. The vas deferens, 20/x in diameter, forms a close coil on each side, which may extend into the hinder half of the segment amongst the large ova. The penial body is of the enchytraeine rather than of the lumbricilline type. It con- sists of a number of pear-shaped masses of gland cells, about eight such masses being visible in a single longitudinal section, and the total number on each side being perhaps in the neighbourhood of two dozen. These gland masses are closely compacted together, separated, however, from each other by, and each individual pear-shaped mass more or less enveloped in, muscular strands; there is no common capsule binding the whole together, and the upper (dorsal) ends of the masses are without covering. The glands are composed of cells derived from the surface epithelium, and discharge on the surface around the small aperture of the vas deferens, which comes to the surface after passing between the glandular masses. The muscular fibres which intervene between the gland masses belong to a numerous series of oblique strands which pass upwards from the neighbourhood of the male pore to the body-wall in the more dorsal part of the segment; a number of such strands occur also in segment xiii. The spermathecal ampulla (Fig. 13) is elongated, pear-shaped, and passes without any sharp demarcation into the duct; it communicates with the oesophagus by a passage, which can sometimes be seen to be patent, and is no doubt always so at some time of the sexual history of the animal; from some of the sections it appears as if the connection with the oesophagus were effected by means of a special diverticulum of the ampulla. The portion
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Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
