116 



PORTUNID^. 



DECAPOD A. 



BHACHYURA. 



FOHTUNIDM. 



HENSLOW^S SWIMMING-CRAB. 



Polyhius Henslowii. Leach. 



Polylms Hensloxvii, Leach, Malac. Brit. t. ix. B. Edwards. Crust. I. p. 4i{9. 



This species, the only one of the genus at present 

 known, exhibits the natatory structure to the greatest ex- 

 tent of any of the British examples of this family. The 

 carapace is remarkably flat, even in the female, and the 

 regions are very indistinctly marked ; it is all over minutely 

 granulated. Its form is nearly orbicular ; the latero-anterior 

 margins, with the orbits and front, forming a semicircle, 

 and the latero-posterior margins being but little contracted : 

 the front is flat, and has five teeth, the external of which 

 on each side belongs to the orbit : the latero-anteiior 

 margin has five flat teeth, the points directed somewhat 

 forwards. 



