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Show 1892.] SPECIES OF EARTHWORMS. 683 Michaelsen1. All of my specimens are excessively small, not measuring much more than an inch in length ; this is about the size given by Michaelsen. They all have the single median oviducal pore, which not only distinguishes the species from the one just defined, but also from every other Benhamia except B. gracilis. This pore lies between the ventral setae of segment xiv. I found the extent of the clitellum to vary somewhat; Michaelsen gives segments xiii.-xx. This was the case with tbe worms from Jamaica and with the single specimen from Seebpore ; in the individual from Dominica the clitellum extended as far as the xxist segment, commencing with the xiiith ; in the specimen from Lagos, on the other hand, the clitellum was less extensive, viz. xiv.-xviii. II. Family CRYPTODRILID^E. 9. Microdrilus saliens (sp. et gen. nov.). I have had about a dozen specimens of this small Earthworm for examination; they were picked out from earth that arrived at Kew Gardens from Singapore; another individual turned up from Java and others from Penang. The small size of the species suggested the generic name ; the largest individuals are in alcohol hardly more than an inch in length. During life the species is, like Perichceta, remarkable for its extreme agility ; when touched they twist themselves violently from side to side and can often spring for a short distance above the table. The worms were preserved in corrosive sublimate and acetic acid, followed by increasing strengths of alcohol, and were investigated by transverse and longitudinal sections. The genus belongs to the family Cryptodrilidae as defined by myself2. Though I have examined a considerable number of individuals, the presence of sand in the intestines spoilt a good many of the sections ; hence m y account of the anatomy of what is in all probability a new genus in less than it should be. As, however, the worm shows one feature of some little interest, I have thought it worth while to add to the present paper such notes as I am able to give. There are two gizzards, which follow each other almost immediately and are only separated by the slightest constriction. In segments xv., xvi., and xvii. lie the calciferous glands ; these have the usual structure and contain large rhomboidal crystals. Their connexion with the oesophagus is interesting ; each pouch does not, as is generally the case, open into the gut ; there is only one duct on each side communicating with the oesophagus. It lies just behind the septum separating segments xv./xvi.; the two remaining pouches of each side communicate with the middle pouch, which alone has 1 " Oligochaeten des Hamburger naturhistorischen Museums, iv.," JB. Hamb. wiss. Anst., Bd. viii. " Terricolen der Berliner zoologischen Sammlung," Arch. f. Nat., Bd. 1892. 2 " The Classification and Distribution of Earthworms," Proc. Boy. Phys. Soc. Edinb. 1890, i. p. 236. |