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Show 670 DR. A. G. BOURNE ON INDIAN EARTHWORMS. [Dec. 21, The nephridia are small and present a unique arrangement. The nephridiopores are all placed on the anterior edge of a somite. They are placed in two rows on each side, an inner and an outer row. The inner row is about in a line with the 11th setae. Counting from the median ventral line, the outer row is about in a line with the 17th setae, while the spermathecal pores are in a line with the 4th setae. In somite iv. there is a single nephridiopore on the left-hand side, in somite v. there is a single pore on the right-hand side, in somite vi. there is a single pore on the left-hand side; these three pores all belong to the inner rows. In somite vii. I found no pore. The remaining somites each present two pores. In somites viii., x., xii., xiv., &c. the pore on the right side belongs to the outer row, and the pore on the left side to the inner row. In somites ix., xi., xiii., xv., &c. the reverse arrangement obtains, viz., the left-hand pore belongs to the outer row and the right-hand pore to the inner row. In too many cases we do not, unfortunately, know the position of the nephridiopore : I have not access out here to the description of Plutellusl, but the nephridiopores are there said to alternate in position ; with this exception the arrangement is unique and bears a most interesting relation to the theory that the spermathecae are modified nephridia. It will be noted that the distances between the outer and inner rows of nephridiopores, between the inner row of nephridiopores and the row of spermathecal pores, and, lastly, between the rows of spermathecal pores, are almost exactly equal, and the pores have exactly similar positions in the somite. I have made no observations on the alimentary canal. There are 45-54 setae in each somite arranged in an almost continuous ring. Setae are present on the clitellum. No modified genital setae were observed. Length 60 millim., circumference 6 m m . ; number of somites 61. Hab. Ootacamund; Naduvatam, Nilgiris. Elevation about 6500- 7500 feet. It is a very strong little worm, and the name refers to its power of leaping into the air when touched. MONILIGASTRIDJE. The huge worm which is mentioned in Darwin's book as occurring on the Nilgiris turned out to be a Moniligaster, a form then known from Perrier's description of a single specimen which he called M. deshayesii. I have since received information that Mr. Beddard has described another species from Ceylon as M. barwelli2. I found, in addition to the large worm, four smaller species of Moniligaster on the Nilgiris, and two others on the Shevaroys or rather at Salem, at the foot of the ghaut. I have thus recognized seven species altogether, but it is exceedingly difficult to characterize these accurately until we know their general organization better, so that I regard the following very scanty descriptions as preliminary. 1 Arcb. de Zool. Exp. t. ii. (1873). 2 Ann. & Mag. Nat. Hist., Feb. 1886, p. 940. |