ORDER DECAPODA. 167 



at its upper extremity, in the manner of a transverse and 

 oblique lamina, closing the ocular cavities- The following 

 articulation is inserted under its superior edge. The testa, 

 seen above, appears, as it were, broadly truncated in front. 

 Its anterior extremity is inclined, and is terminated by a sort 

 of hood, or denticulated bill. {Cancer cristatiis, Linn.) 



Stenocionops, Leach, 



These are distinguished from all the subgenera of this tribe, by 

 their long, narrow, ocular pedicles, projecting very much out 

 of their fossets. {Cancer cervicornis, Herbst.) 



Sometimes the under part of the feet presents neither ranges 

 of denticuiations nor fringes of hair, like a knob ; those of the 

 first pair at least exceed the testa in length by one half, and 

 often by a much greater proportion. The body is generally 

 shorter than in the preceding, either globular, or in the form 

 of a contracted egg. 



A crustaceum of this tribe {Maia retuja, Coll. du Jardin du 

 E/oi), whose testa is an ovoid, truncated, or blunted in fr'ont, 

 and woolly ; whose ocular pedicles, elongated, and very much 

 bent, proceed to lodge themselves behind, in fossets situated 

 under the lateral edges of the testa ; whose carpus, as well as 

 in the maise, is elongated, offers another character which dis- 

 tinguishes it exclusively : the length of the feet, beginning 

 from the second, appears to augment progressively, or at least 

 to vary but little. Dr. Leach has formed of it the genus 



Camposcia. 



In the others, as usual, the length of the feet diminishes pro- 

 gressively, from the second pair to the last. 



We are acquainted with some whose ocular pedicles, 

 though much shorter than those of stenocionops, are always 

 projecting ; whose lateral antenna? have the third articulation 



