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Show 224 DR. W. B. BENHAM ON [Nov. 15, Dorsal vessel double; last heart in 13th segment. Gizzard large; (esophagus with 3 pairs of glands, quite distinct and typically developed, situated in segments 13, 14, 15, the last more dorsally placed and smaller than the preceding. Sperm-sacs of fair size, in segments 11, 1 2 ; botryoidal. Prostates* normal. Penial chsetse delicate, much curved in an exaggerated S-slia.pe, with the tip spoon-shaped, though[pointed and curved in side view. The spermathecce are of peculiar form (text-fig. 41, p. 22o). Each consists of a bilobed sac ; the two lobes are of about the same size and irregularly ovoid, and joined by a short, narrow isthmus, whence the muscular duct originates. One might imagine that one lobe is a " diverticulum " in the usual sense, but examination •of stained specimens shows no structural difference between them ; Text-fig. 43. Maoridrilus mauiensis.- Tip of penial chaeta, side view ( X 350. Oc. 1, obj. 7, camera). Text-fig. 44. Maoridrilus mauiensis.- Tip of penial chteta ; view of plane at right angles to the above (? perhaps the extreme tip is injured). the epithelium is folded, irregular, and apparently glandular, as a quantity of stained material is present in the lumen; I could see no spermatozoa. As a rule, there is a marked difference in structure between sac and diverticulum. Unfortunately the specimen is not sufficiently well preserved to enable me to decide this question. At any rate the form of the spermatheca and the arrangement of the oesophageal glands mark the species from any of those hitherto described. This is the first species of Maoridrilus described from the North Island, and is the only specimen amongst the material I have received from various correspondents collected in several widely scattered districts. * No doubt Beddard's term " spermiducal gland' ' is in some respects better, but it is a clumsy term, and when " duct" is added it is by no means euphonious. |