AUSTRALIAN CLADOCERA. 



24th of the same month, and submitted to closer examination, a care- 

 ful coloured drawing being made from life. The embroys in its ma- 

 trix were already comparatively advanced in development, exhi- 

 biting quite perceptibly as they did all of the limbs and likewise 

 the eyes as yet distinctly separated; the specimen was moreover 

 provided with large greenish coloured ovaries containing ma- 

 terial for another brood. — In habits and mode of locomotion 

 this form agrees exactly with the preceding species. 



Occurrence. — The mud that yielded the present form, was 

 a small quantity of the same material from which the above- 

 described interesting- form of Sididse, Lafmwpsis mitt ml is, had 

 been hatched. Though I apportioned several parcels of this mud 

 among different aquaries, no other specimens of the present 

 species were developed. -- According to Mr. King, the species 

 is widely distributed throughout New South Wales, having been 

 found by that author at Sydney, New Town, Paramatta, the 

 Cowpastures, and in the River Karuah, near Stroud, Port Ste- 

 phens. It may however be questioned whether perhaps some 

 of these localities do not more properly refer to the preceding 

 species. 



Fa m. LjiHcodapliHidw. 

 Gen. Macrothrix, Baird. 



4. Macrothrix spinosa, King. 



(PL- 3). 



Macrothrix spinosa, King, On Australian Entomostracans. 1. 

 c - P- 256, PI. VL E. 



Specific Characters. — Carapace of adult female, as seen 

 laterally, rounded oval, dorsal edge boldly arched in the pos- 

 terior part, ventral subangulated in front of the middle and 

 obliquely ascending posteriorly, extremity obtusely pointed. Head 

 rather large, snbtriungiilar. semierect. rostral projection slightly 

 prominent, obtuse at the tip. Shell obscurely reticulate, dorsal 



