178 Annals of the South African Museum. 



Elassoneuria trimeniana, Eaton, Ent. Monthl. Mag., vol. xvii., 

 1881, p. 191 ; Trans. Linn. Soc., Lend., 1888, p. 32, pi. iii., 3. 



Of this interesting species, of which only the female is known, 

 there were six specimens in the Collection, all females. They 

 were taken at M'fongosi, Zululand, March, 1911, by W. E. Jones. 



As the descriptions given by MacLachlan and Eaton are very 

 short, I add a few supplementary notes. 



Head and thorax pale brown. Eyes black. Ocelli white, sur- 

 rounded by black. The basal joint of the antennae pale brown, the 

 bristle black. Abdomen white with a faint yellowish tinge. All the 

 dorsal segments with a small purplish brown hind border and a 

 lanceolate median spot, which does not touch the front or hind 

 border of the segments. The underside white with a small yellow 

 spot in the middle of each segment and with yellow lateral margins. 

 Setae and legs white. 



Length of body, 16-20 mm. ; forewing, 17-22 mm. 



GEN. POLYMITAECYS, Eat. 



POLYMITARCYS CAPENSIS, Sp. nov. 



Subimago $ . Head and thorax light violet-grey. The ocelli 

 white, surrounded by a black circle ; the eyes jet black. On the 

 prothorax two dark spots near the front margin ; front angles 

 and lateral margins reddish violet. Meso- and rnetathorax yellow- 

 ish brown, with a fine reddish violet median line. Abdomen 

 ventrally white, dorsally whitish with a faint reddish tinge, which 

 becomes strong reddish yellow on the last two segments. From the 

 front border of each segment two lunate spots extend backwards a 

 little farther than the middle of the segments. The two spots do 

 not touch each other. Forceps white ; penis yellow. Fore femora 

 and tibiae greyish black ; tarsi and underside of femora whitish. 

 Intermediate and hindlegs pale yellowish. Wings white with a 

 faint ash-grey tinge. Neuration opaque, and the costa, subcosta, and 

 radius in forewing with violet-greyish tinge. 



Subimago. ? . Setae white and very pilose. 



Length of body : $ , 13 mm. ; ? , 14-15 mm. Setae : ? , 13 mm 

 Wing : $ , 13 mm. ; ? , 15 mm. 



One male and five females (all subimagines). 



M'fongosi, Zululand, December, 1911. 



In " A Ee visional Monograph of Recent Ephemeridae or Mayflies " 

 (Trans. Linn. Soc., Lond., 1888), p. 45, A. E. Eaton mentions a 



