250 Records of the Indian Museum. [Voi,. X, 



from the head and clothes the remainder of the oesophagus ; is 

 exceptionally developed. Ocelli two in number, diameter of the 

 ocellus 0*009 ^ni ; distance of ocelli from the head 0*56 mm. 

 They lie on the outer surface of the oesophagus immediately 

 dorsal to the lateral lines ; colour, V:)lack with a tinge of red. Two 

 lines of fine red-black granules extend backward for a short dis- 

 tance from the ocelli. 



I^ateral organs as described above. 



The Excretory System. — Excretory glands not distinguish- 

 able, but may exist in the mass of collar cells. No opening of 

 the ventral gland distinguished unless a slight mark in the ventral 

 line opposite the nerve ring represents the pore. 



Male Reproductive Organs. — The fundus of the anterior testis 

 lies 17 mm. distant from the head. Testes double ; remainder of 

 tract single. vSpicules two, of the form indicated in fig. 13 of 

 PI. xxxi, hollow. A single accessor}^ piece. 



-1-32— 1-32— 1-55 — 17 



Cobb's Formula — d' 



-578— i578-5o"<^ —98-4 



Monhystcra megalaima, sp. nov. 

 (PI. xxxii, figs. 21 — 27.) 



Indian Museum No. ZEV. 6237-7. Among filamentous algae 

 at edge of lake, Chilka Lake, Gantasila. 19-4- 14. One male, 

 one female, mounted in glycerine-jelly-formalin. 



Measurements, see Table I. 



Female. — A delicate organism. Bodj^ tapering only very 

 slightly to the head, the posterior extremity tapers gradually from 

 a short distance in front of the vulva ; tail pointed but not filiform, 

 wiih a permanent ventral curvature. 



Head marked off from the body by a slight annular constiic- 

 tion ; anterior surface flatly rounded (PI. xxxii, figs. 22, 23) ; a 

 circle of stout bristles, six in number, surrounds the head ; length of 

 bristles 0"0I36 mm. ; internal to this ring is a second ring of very 

 short spines. No lips or papillae. Lateral organs large, circular, 

 o-oo88 mm. in diameter; their anterior margin 0-0187 mm. from 

 the head, a distance approximately equal to the breadth of the 

 head. Mouth capsule oval, transverse, walls delicate ; no teeth 

 or cuticular thickenings. 



Cuticle marked with very fine transverse rings from head to 

 tail ; the rings extend throughout the thickness of the cuticle. 

 Hairs scanty, scattered irregularly, of remarkable length (o'02 

 mm., i.e. more than half the breadth of the body) and tenuity, 

 sometimes spirally curled. No papillae. 



Lateral lines and muscle fields not distinguishable. 



Tail, see PI. xxxii, fig. 24 ; a circle of short bristles close to 

 the tip, no bristles at the anus or vulva. No glands or papillae. 



Oesophagus simple, club-shaped, no bulb or division ; a trans- 

 verse diaphragm in the muscular substance at a level immediatel}^ 



