A NEW SPECIES OP MONILIGASTER PROM INDIA. 363 



{d) The septa vi/vii, vii/viii, viii/ix are thick, but not 

 so thick as in other species. 



(e) Gizzard occupies Somites xiii, xiv, xv, xvi, with 

 annular bands separating the four muscular regions. 



(/) Atrium (prostate) large, spherical, lying in So- 

 mite XI. 



(g) Spermatheca nearly spherical ; the duct opens to 

 the exterior through a muscular sac, subdivided into 

 an anterior and a posterior lobe by the septum 

 vii/viii. 



Description of M. indicus, n. sp. 

 I. External Anatomy. 



The size of the present species has just been stated, and it 

 appears to be of some importance, as there is a great range 

 amongst the species; for example, M. japonicus and M. 

 Barwelli is only 28 mm., M. Deshayesi 150 mm., whilst M. 

 Houtenii attains the length of one and a half metres. Of 

 Bourne^s seven species, only M. ruber is definitely measured, 

 its length being 100 mm. 



As in all other species, with the exception of M. sapphi- 

 rinaoides, no clitellum was present; the worm was evidently 

 not quite sexually mature, as deduced from the condition of the 

 genital organs. As Beddard (5) and myself (6) have previously 

 suggested, the clitellum may be a more transient structure than 

 in other macrodrilous Oligochseta; and it would be very interest- 

 ing, and even important for systematic purposes, to know the 

 minute structure of the clitellum in Bourne's, species. Does it 

 agree more closely with the microdrilous clitellum, or is it 

 several cells thick, as in Lumbricus, &c. ? 



The colour of the worm during life is unknown to me. In 

 the spirit specimens the dorsal surface is very much darker — a 

 greeny brown — than the ventral and lateral surfaces ; there is 

 a very sharply marked line of separation between the two 

 colourings, and not a gradual paling out as in many other 



