Fresh-Water Entomostraca from China and Sumatra. 9 



produced, cervical depression well marked. Carapace very 

 tumid, seen laterally, oval quadrangular in outline, being 

 transverse^ truncated behind, ventral edges of valves straight, 

 slightly angular in front, and each produced behind to a spini- 

 form projection of moderate length. Sculpture of shell rather 

 coarse, consisting in the posterior part of very conspicuous 

 curved transverse ridges running parallel to the hind edge, 

 anterior part of valves likewise coarsely ridged, the ridges 

 being partly crossed by wavy longitudinal striæ. Eye large, 

 with very conspicuous crystalline bodies, and, seen dors- 

 ally or ventrally, exhibiting its original duplicity very dis- 

 tinctly. Ocellus small and occurring near to the tip of the 

 rostrum. Antennulæ small, knob-like. Antennæ and legs of 

 the usual structure. Caudal part comparatively short and 

 broad, with only 4 pairs of anal denticles, terminal claws 

 of moderate length and smooth. Ephippium of the usual 

 appearance. 



Male much smaller than female, and on the whole 

 resembling that of S. mucronata. 



Colour very dark brownish gra}^, in some places nearly 

 black. 



Length of adult female 076 'i^"% of male 0'40 ™™. 



Remarks. — The above-described species is unquestion- 

 ably identical with the Australian form recorded by King 

 as Daphnia mucronata. It is certainly very nearly allied 

 to the European species, but apparently specifically dis- 

 tinct, differing, as it does, not only in the much smaller 

 size, but also in the shape of the head and in the less 

 sharply angulated anterior part of the valves. The sculp- 

 ture of the shell is, moreover, much coarser than in the 

 European species. 



