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Show 546 MR. F. E. BEDDARD ON THE [June 23, anterior segments of the body. In both species of Notoscolex the nephridia appear to be much the same, as also in Didymogaster : in these genera the description of the nephridia agrees fairly closely with what appears to be the characteristic features of these organs in Perichata, at least in those species in which they have been observed. In my species of Cryptodrilus the nephridia are entirely different, and conform to the type that is met with in many species of Earthworms, including Microchata and certain species of Acanthodrilus1. These organs in Cryptodrilus fietcheri consist of a complicated coil of glandular tubules, the details of which I have not worked out, but which appears to bear every resemblance to the corresponding part of the nephridium of Lumbricus, opening on to the exterior by a sac-like muscular duct, which is furnished at its extremity with a short diverticulum of identical structure. Another fact of importance about the nephridia of this species is that their orifices are not fixed ; like those of Acanthodrilus nova zelandice and A. dissimilis and of Plutel/us, the nephridia of Cryptodrilus fletcheri alternate in position from segment to segment. The position of the orifices, however, always corresponds to one of the setae and may be placed in front of either of the dorsal pair, which have been already stated to be widely separated in this worm. Sometimes the position of the nephridial pore corresponds to the outermost of the two ventral setae, but I have never observed the nephridial pore to be situated in relation to the ventralmost seta. In one specimen which I studied by means of transverse sections the nephridia appeared to commence in the second segment. In this and the two following segments the nephridiopores were placed in front of the dorsal seta; in the next three segments the nephridiopores have a similar relation to the ventral setae of the lateral pair; in the ninth segment the pores were asymmetrically disposed, being on one side of the body in front of the outermost seta, on the opposite side in front of ventral seta of dorsal pair. In some of the succeeding segments the asymmetrical disposition of the nephridiopores was also found ; in this particular character Cryptodrilus agrees with the other species referred to. The difference in the nephridia of this species and of C. rusticus is not, in the present state of our knowledge, sufficient reason for separating the two forms generically ; precisely similar differences are to be seen in Acanthodrilus. Reproductive Organs. The seminal vesicles (testes) in the specimen that I dissected have the very anomalous arrangement recorded by Fletcher ; that is to say, a pair is placed in segments 9 and 12, the intermediate segments not being occupied by these structures. The ciliated rosettes lie in segments 10 and 11. The same segments contain tbe testes, which are precisely similar in position and in structure to those of other Lumbricidae. An 1 P. Z. S. 1885, p. 810. |