12 G. O. Sars. 



by Mr. Whitelegge. It was taken from a pond off Botany 

 Road, near "Waterworks Bridge, on the 6th April. 1895. 

 Distribution. Queensland (G. O. Sars). 



4. Simocephalus acutirostratus, (King). 

 (PL 2, figs, 1-3). 



Daphnia Elisabethœ, var. acutirostrata, King, 1. c. p. 254, 

 PI. VI, C. 



Specific Characters. Shell, seen laterally, oblong 

 oval, terminating posteriorly in a rather prominent, obtusely 

 conical prominence, slightly denticulated at the tip, and 

 extending somewhat above the longitudinal axis, dorsal 

 margin forming a perfectly even curve throughout. Head 

 comparatively small, procumbent, with the front produced into 

 an acute deflexed projection, ventral edge straight, ob- 

 liquely ascending, rostral projection small, deflexed. Eye of 

 moderate size; ocellus very small, punctiform. Tail rather 

 broad, forming, above the anal sinus, a gibbous expansion, 

 anal denticles about 12 on each side, terminal claws with 

 a series of well-marked secondary teeth. Length attaining 

 3 mm. 



Remarks. This form has been recorded by Mr. King 

 as only a variety of his Daphnia Elisabethœ. It is, how- 

 ever, quite certainly, as justly pointed out by Mr. Schoe- 

 deler, a very distinct species, exhibiting, as it does, several 

 well-marked differences from all the other known species 

 of the genus. The specific name acutirostratus is somewhat 

 inappropriate, since it is not the rostrum, but the front, 

 which is acutely produced. According to the laws of prior- 

 ity, however, this name, as the older one, must be preferred 

 to that proposed by Schoedeler, viz., paradoxus. 



