52 



a. o. SAES. 



parallel to the anterior edges. A partial crossing of the striae 

 on the intervening space of the valves may also he observed in 

 this species. The inferior edges of the valves are throughout 

 their entire length fringed with a dense row of cilia, somewhat 

 coarser and more elongate than in the preceding species. At 

 the infero-posteal corners occur 2 dentiform projections, which 

 however are so very minute as easily to escape attention. 



The eye is rather small and of a structure similar to that 

 in the preceding species. 



The ocellus is even a trifle smaller and located nearer to 

 the eye than to the tip of the rostrum. 



The antennulae are rather narrow, conical in form, and, as 

 usual, besides the apical sensory filaments, provided anteriorly 

 with a single delicate bristle at a short distance from the tip; 

 they do not reach to the apex of the rostrum. 



The tail (fig. 9) is considerably dilated in its outer part and 

 at the extremity broadly truncate, with the anterior corner pro- 

 jecting less than in the preceding species. The dorsal edge ex- 

 hibits in its outer half a fine ciliation, and at some distance 

 from the edge a lateral series of about 10 very delicate appres- 

 sed and somewhat lamellar denticles may be distinguished. There 

 is no trace of any angle below the anal orifice, but above it a 

 very slight angular projection occurs, forming the beginning of 

 a strongly chitinized stripe running along the remainder of the 

 dorsal edge. The caudal claws are relatively a little shorter 

 than in the preceding species and less evenly curved; the se- 

 condary denticle at their base is extremely small. 



The colour of the animal is pale yellowish brown or corne- 

 ous, the body being as usual somewhat darker than the shell. 

 The ova contained within the incubatory cavity exhibit in the 

 centre of the bright greenish yolk a rather large orange-coloured 

 oil-vesicle. 



Observations. — Of the present form I have had opportunity 

 of observing only a single specimen, an adult ovigerous female, 

 which I accidentally got up in the dipping tube on the 26th 

 July 1886 when searching for other Entomostraca. Although 



