STUDIES IN AUSTRALIAN CRUSTACEA — McCULLOCII. 331 



low tubercles. Gastric region greatly swollen, almost or quite 

 smooth. Two prominent tubercles between the eyes. Rostrum 

 more or less obliquely deflexed, more so in females than males, 

 and formed of two rather thick, widely diverging spines, which 

 are about as long as the distance from their base to the hinder 

 orbital margin. Orbits without an anterior spine; posterior 

 spine present and sometimes preceded by a very small notch. 

 No post-orbital spine. 12 Eyes of moderate length, and with a 

 small, distal tubercle. Hepatic region with two diverging 

 spines of which the anterior is much the larger and usually has 

 a small tubercle on its front margin ; latero-inferior surface 

 with a small tubercle. -Basal joint of the antenna much longer 

 than broad with a long denticulate spine at its antero-exterior 

 angle projecting obliquely forward, and visible from above ; 

 flagellum stout, nearly twice as long as the rostral horns and 

 wholly visible from above. Merus of external maxilliped with 

 its antero-exterior angle forming a rounded lobe, its front 

 border slightly emarginate ; flagellum articulated at the antero- 

 internal angle. Pterygostomial regions each with a prominent 

 tubercle, and there is a smaller one before each anterior angle of 

 the buccal cavern. 



Arm of cheliped with obscure tubercles of which the most 

 prominent are two or three on the median line above ; a large 

 compressed distal spine or lobe. Wrist with an obtuse crest on 

 the outer surface in the male, rounded in the female. Palm 

 compressed, smooth, much longer than broad, its edges rounded ; 

 fingers rather long and slender though shorter than the palm, 

 curved, finely denticulated and acutely pointed. Ambulatory 

 legs of moderate size, decreasing in length backwards. The 

 penultimate joints only very slightly dilated and provided with 

 long, coarse, curved setse on their lower surfaces ; dactyli rather 

 long, curved, with a double row of spinules on their inner 

 margins. 



Abdomen of the male consisting of seven segments, of the 

 female, five. 



Described from six specimens, one male 12 mm. long being 

 the specimen figured, and 6ve females 14-18 mm. long. 



This species is allied to Naxia tumida, Dana, from which it 

 may be readily recognised by having the penultimate joints of 

 the ambulatory legs much less dilated and the gastric region 

 smootli, not tubercular. 



13 I consider that the second posterior orbital spine mentioned by 

 Haswell belongs to the hepatic region. 



