752 Records of the Indian Museum. [Vol. XXII, 



■angle, that on the outer side of the curve of the shaft being rather 

 longer and perhaps slightly stouter than the other (fig. i). 



Remarks. — In the absence of the posterior end of any of 

 the specimens, there is no strict proof that they ma}' not belong 

 to the genus Dero or Aulophorus , which have gills around the anus, 

 though their setal characters are similar to those of Nais. The 

 existence of a long region of newly budded segments posteriorly, 

 however, is very suggestive of Ndis paraguaycnsis ; and it is 

 difficult to imagine developed gills at the hinder end of a series of 

 rudimentary or still undiiJerentiated segments. 



The three varieties of Nais paraguayensis form a series 

 distinguished by the relative sizes of the inner and outer prongs 

 of the dorsal needles : — 



N. paraguayensis lypica .... outer prong considerably smaller. 

 J, ,, var. aequalis . . . .prongs equal. 



,, ,, var. &«rAMffi'»SiS. .. .inner prong smaller. 



The difference between the typical form of the species and 

 the present variety is such that, but for the existence of the 

 intermediate variety aequalis, it would have been necessary to 

 separate them as distinct species. 



Gen. Btanchlcdrilus, Mich. 



Branchiodrilus sp. 



Burhanpui-, Central ProviriLc-'j. 4-6-iii'i9icj. F. H. Gravely. A small 

 fragment, in a tube with Aulodi-ilits reniex. 



The fragment was incomplete at both ends, and the species 

 therefore indeterminable. 



Branchiodrilus menoni, Stepli. 



Madras, Prof. K. Ramunni Menon's collection 5-iii-igi2. Seven speci- 

 mens or fragments, in a tube with two specimens of Branchiiira soiverbyi. 



One specimen was undergoing fission, but showed no budding 

 zone ; the gills of the posterior animal began immediately behind 

 the point of impending separation. The heads of the other 

 specimens showed a prebranchial region of varying extent, some- 

 times small, sometimes comprising four seta-bearing segments. 



Fam. TUBIFICIDAE. 

 Gen. Branchiura, Bedd. 

 Branchiura sowerbyi, Bedd. 



Northern portion of Loktak Lake, Man'pur, Assam: 260(1 ft. l6-i7'ii' 

 1920. Three specimens. 



l^oktak Lake, Manipur; on ]'ivipara lecythis. i7'ii'i()2o. .A single 

 specimen. 



Off Thanga Island, Manipur. 24Mii'i920. Three specimens, all frag- 

 ments, two probably comprising togetlier one individual. 



Madras, Prof, K. Ramunni Menon's collection. 5'iii'i9i2. Two speci- 

 mens. 



