76 



LEACH'S PORCELLANA. P. Leaehii, Gfa/s Zool. 



Misc., p. 15. Common. 



Beside these I possess aspcimen of a minute species which, 

 though much resembling; the latter, yet differs from it in seve- 

 ral particulars. The Carapace advances further in front, 

 where it is divided into three scarcely separated portions, 

 somewhat resembling the P. Longicornis : and retiring from 

 this it turns off angularly towards the eyes. On the ridge of 

 the second section of the handlegs are two well marked spines ; 

 the three remaining are rather shorter than in the last species 

 and margined thinly .with hairs, whereas in the other they are 

 smooth. I found this specimen on a coralline from deep water, 

 and in ignorance of its being hitherto described, I have pro- 

 visionally named it 



P. Acanthecheles. Couch's M.S. and fig. 



FAMILY of MACROURES. 



This is divided into the following sections : 

 CUIRASSIANS: crust remarkably thick and hard; cara- 

 pace depressed and wide ; without a moveable scale below 

 the second pair of antennae. 

 ASTACIANS: crust firm; body lengthened and somewhat 

 compressed ; abdomen large, but less developed in propor- 

 tion to the thorax than in the salicoques ; a moveable scale 

 below the outer antenna?. 

 SALICOQUES: the body compressed laterally; abdomen 

 large, its covering horny ; scale below the outer antenna? 

 lar^e, the natatory false legs covered by the lateral enlarge- 

 ment of the abdominal rings. Caudal fan large. 



The Cuirassians are further divided into the following 



sub-families : 



GALATHEANS: fifth pair of legs slender and not fit for 



walking, but bent up under the base of the preceding. 

 LANGOUSTIANS : fifth pair of legs as the others, and not 

 bent up ; hands with an imperfect finger, the other iegs 

 without that organ. 



GALATHEANS. 

 GENUS GALA THE A : the carapace covered with trans- 

 verse sections edged with short hair ; snout advanced and 

 spinv ; half ot the abdomen permanently bent under. 

 PLATED LOBSTER. G. Strigosa. M. Edwards' Crust , 

 vol. 2, p. 273. G. Spinigera, Leach's Malac, pi. 28. Pen- 

 nant, pi. 14, fig. 26. 



Common and in its younger state not easily distinguished 

 from the next species. It is incapable of any motion but 

 backward, and rarely rises above the bottom, where by a la- 

 borious motion of its tail il contrives to retreat from its ene- 

 mies; but its usual progress is creeping, and by the Wgs only. 



