188 ON SOME NEW AUSTRALIAN MARINE ISOPODA, 



pointed. From Z. diadema it differs in not having the process of 

 the last thoracic segment terminally dilated. 



Zuzara emarginata, sp. nov., Plate III., fig. 5. 

 Surface nearly smooth, very finely punctate. Head rather 

 prominent, narrowing gradually towards the front. First segment 

 of the thorax not quite so long as the two following taken together; 

 sixth segment as long as the first ; seventh segment very large, 

 nearly concealing the abdomen ; median posterior process very 

 long, extending far beyond the extremity of the abdomen, slightly 

 curved downwards, emarginate at apex — a prominent, acute tooth 

 on either side of the segment near the base of the process. Last 

 segment of the abdomen with a rounded swelling on either side. 

 Terminal notch deep — about one-sixth of the width of the abdomen ; 

 mesial lobe very prominent, extending beyond the boundaries of 

 the notch, truncate and faintly emarginate. Basal joint of the 

 internal antennae very large, notch for second joint wide with a 

 prominent tooth on either side ; third joint slender, not longer 

 than the second, flagellum shorter than the peduncle. Outer 

 antennae much longer than the inner, more than a third of the 

 length of the body, fourth and fifth segments of the peduncle 

 subequal, flagellum longer than the peduncle. Outer ramus of 

 uropoda subovate — the outer border nearly straight, the inner 

 convex, the apex subacute ; inner ramus of about the same length 

 as the outer, bent directly backwards about the middle of its 

 length, apex subacute ; both rami fringed with hair. Colour 

 light red with darker spots on the thorax. Length £ inch. 



The females and young males have the seventh thoracic segment 

 small, the posterior process short or absent, the mesial lobe less 

 prominent, and the uropoda relatively smaller. 



Eab. Griffiths' Point, Western Port. 



This species is apparently a tolerably near ally of Cymodocea 

 armata of Milne-Edwards*- (from Australia), but in the latter 

 * Mist, nat. Crust., tome 3, p. 215, pi. 31, fig. 16. 



