STALK-EYED CRUSTACEA 197 



I. Portunus. 



Portunus . . Fabricius, the Milne Edwards, Miers. 

 Liocarcinus . De Ilaan, Stimpson. 



Carapace moderately transverse, depressed, with the 

 lateral margins arcuated, and armed with five regular and 

 even teeth: the front of moderate width, and divided into 

 several lobes or teeth, which are not very prominent ; the 

 last tooth scarcely, if at all, exceeds the preceding one in 

 length. The eyes are set on very short thick peduncles. 

 The orbits are not large, and have two fissures in their 

 superior, and one or two on their inferior margin. The 

 basal antennal joint is short and but little dilated ; it is 

 generally united with the frontal margin, but does not 

 always completely fill the interior hiatus of the orbit. The 

 third joint of the external maxillipedes is not produced at 

 its antero-internal angle ; the fourth is truncated or very 

 slightly rounded distally, with the antero-internal angle 

 scarcely, if at all, emarginate, and the antero-external 

 angle not produced. The ridges of the palate are not 

 always developed. The legs of the first pair are subequal 

 and moderately developed ; the fourth joint (arm) is 

 smooth, without spines, the fifth joint (carpus, wrist) 

 has a strong spine on its inner margin, palm with a 

 spine near to the distal extremity of the superior margin, 

 and usually somewhat indistinctly costated on the exterior 

 surface. Walking legs of moderate length, with the last 

 joint styliform ; fifth pair has the two last joints dilated 

 and compressed ; the last joint ovate. 



The abdomen is five-jointed, the third to the fifth 

 segments being consolidated. 



Range. — Mediterranean Sea, Atlantic Ocean, Aus- 

 tralia, Japan. 



