252 Proceedings of the Royal Society of Victoria. 



long white setae ; sculpture not so strongly marked as in the 

 preceding variety and without any nioniliform appearance. 



2. Esthepia elliptica, G. O. Sars. (PI. XXXVI. Fig. B). 



Arch, for Math, og Naturvid, Christiania, xix., No. 1, pp. 12- 

 17, pi. 2. 



Specific Characters, Female. — Shell, seen laterally, of a rather 

 regularly elliptical form, anything but equilateral, the umbones 

 placed far in front, dorsal margin behind the umbones nearly 

 straight, and not angular behind, free edges of valves evenly 

 curved throughout, both extremities being rounded and nearly 

 equal, though the anterior one appears a little more obtuse than 

 the posterior ; seen from above, rather tumid, greatest width in 

 front of the middle, posterior extremity more pointed than the 

 anterior. Valves of rather firm consistency, with 14 very 

 strongly marked and elevated, ridge-like, concentric lines of 

 growth, each provided in their posterior part with short, stout 

 bristles, surface between the lines finely and irregularly reticulate, 

 marginal area rather broad, and furnished with numerous densely 

 crowded concentric striae, which are not at all raised. Upper 

 surface of head bent at nearly a right angle close to cervical 

 impression, rostrum somewhat blunted at the tip. Number of 

 legs, 22-23 pairs. Tail of usual shape, with a single pair of 

 dentiform projections at the base dorsally, caudal plates produced 

 beneath into strong unguiform processes, and each having along 

 the dorsal edge numerous (from 20-30) denticles of unequal size, 

 caudal claws slender, without any setae at the base, but having 

 their outer part distinctly denticulated along the concave edge. 

 Colour, dark reddish brown. Lengtli of adult female scarcely 

 exceeding 5 mm. (G. O. Sars). 



Locality. — Near Roebuck Bay, West Australia (G. O. Sars). 



3. Estheria sarsii, sp. nov. (PI. XXXV., Figs. 1 a-f). 



Description of Male. — Shell moderately tumid, of firm consis- 

 tency, seen from the side ovoidal, umbones much nearer the 

 anterior than posterior margin, very wide, and extending very 

 much above the dorsal line. Dorsal hinge considerably longer 



