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Show 682 MR. F. E. BEDDARD ON N E W [Dec. 20, the space between the ventral pairs of setae, where there is no development of the clitellum at all. The setae are strictly paired and are all ventral in position; the distance between the two ventral pairs is about half again as great as that between a ventral and a lateral pair ; there is no specialization of the setae anywhere except upon the xviith, xviiith, and xixth segments ; the ventral pairs of setae are absent from all of these segments; on segments xvii. and xix. their place is taken by the penial setae. I have already commented upon the apparently universal absence of the ventral setae of segment xviii. in the genus Benhamia. Between segments viii./ix. and ix./x. there is a single oval papilla lying in a position which corresponds to the interval between the two ventral pairs of setae. The oviducal pores lie in front of the outer of the two ventral setae on each side. The alimentary canal has two gizzards ; there are the usual three pairs of calciferous glands in segments xv., xvi., xvii.; that section of the oesophagus from which they arise is of a very narrow calibre ; but from the xviiith segment the alimentary canal widens out very greatly and forms a dilated and thin-walled region without any typhlosole, which should perhaps be reckoned as belonging to the oesophagus. The intestine proper begins in segment xxii.; the buccal cavity is remarkable for the fact that it has a short caecum on the dorsal surface, which differs from the rest of the buccal cavity in the character of its lining epithelium ; the cells which constitute the innermost layer of this caecum are like those of the epidermic layer; the cells are of two kinds, there being among them cells with clear contents and not staining deeply with borax carmine, which are exceedingly like the gland-cells of the integument. I comment later upon the similarity which this worm shows in the said particular to a representative of a totally distinct genus (Microdrilus ex fam. Cryptodrilidae). The nephridia in the posterior part of the body, that is to say behind the clitellum, are enveloped in a thick mass of vesicular cells, a condition which is very common among tropical Earthworms ; the nephridia are of course " diffuse," and there is a mucous gland. The reproductive organs show one peculiarity not common among Earthworms-the terminal part of the vas deferens is ensheathed in a muscular coat of some thickness ; it is only from the xvith segment to the opening of the tube that this muscular coat is to be seen; the penial setaa are wavy at the extremity, being bent into a spiral with not very close coils; on the last bit of the seta are a very few denticulations with their apices directed forwards. From Lagos I have also received examples of what I believe to be Michaelsen's Benhamia bolavi; this same species has also turned up from Dominica, Trinidad, Jamaica, St. Vincent, and, more remarkably still, from Seebpore, near Calcutta. I cannot distinguish any of these individuals from Benhamia bolavi as described by |
