BY G. I. PLATFAIR. 129 



Long. coip. 26, hit. 10—12, lat. ap. 3, long. caud. 3 — 4^. Auburn (135) ; 

 Guildford (1461; Wyrallah; Lismore (236, 259, 293). 



A broadly elliptical, practically oval form, without any anterior prominence 

 (none observed at any rate), but slightly flattened in front; Ijehind furnished 

 with a very short triangular tail; membrane costate longitudinally, with 8 — 10 

 costae visible. 



Var. OBESA, n.var. (PI. vi.. fig. 9). 



Forma prae longitudinem erassior. 



Long. coil?. 26, lat. 14 — 15, lat. ap. 3, long. caud. 3 — 4^. Lismore (242, 

 236. 237). 



Lepocincus paxillipoumi.s, n.sp. (PI. vi., figs. 10, 11). 



Forma minima, corpore conico, fronte late rotundata, prominentia nulla ; 

 postice attenuata, cauda minuta praedita. 



Long. 20, lat. 8;^. Guildford (114); Pott's Hill (113). 



A small Lepociiiclis, somewhat conical in general shape, broadly rounded in 

 front, narrowed behind and furnished with a short tail, no anterior prominence 

 noted. A rare species. 



Lepocincllsi rugulosa, n.sp. (Text-lig. 3/, m). 



Forma cylindracea, polls late-rotundatis, lateribus parallelis; membrana 

 striis (vel costis) oblicjuis spiralibus ornata. A vertice circulata, raargine 

 rugulosa. 



Long. 25, lat. 15/i. Kookwood. 



A small cylindrical fomi with straight sides and broadly rounded ends. 

 Membrane striate obli(|uely and spirally either with coarse striae or fine costae. 

 End view circular, the striae showing as about 15 small corrugations on the 

 margin. I am a little doubtful about the genus, as I have no note on the cell- 

 contents. The flagellum figured, however, is Euglenoid and not as in Spheno- 

 monas, and the motion "continually revolving" agrees with Lepocinclis. Noted 

 in (Quantity from Rookwood in 1910. 



Genus Trachelomonas Ehr. 



A detailed a(!count of the principal types of this genus occurring in our 

 waters has already been given in "The Genus Trachelomonas" (These Pro- 

 ceedings, 1915). Here it will only be necessary, therefore, to describe forms 

 noted since then, and to confirm those of rare occurrence by new records. 



Trachelomonas volvocina var. planktonica, n.var. (PI. vi., fig. 12). 



Forma collo exteriore distincto instructa. A distinct neck round the ori- 

 fice is very rare in this species. Only noted twice, in both cases from water- 

 supply samples. 



Diam. 15; coll. lat. 3, alt. 2^. Brisbane Water Supply; Sydney Water 

 Supply (115). 



Var. SCABRA, n.var. (PI. vi., fig. 13). 



Forma collo brevi; membrana aspera. The membrane is usually very smooth 

 and shiny; in this form it is slightly rough with minute irregularities, not regu- 

 larly granulate; a short neck present. 



Diam. I2ja. Guildford (45). 



