DECAPODA. 45 



long and slender ocular pedicles which protrude from their fossu- 

 lae(l). 



There, the under surface of the feet presents neither ranges of den- 

 tations nor claviform cilia. Those of the first pairs, at least, are one 

 half longer than the shell, and frequently much longer. The body 

 is usually more abbreviated than in the preceding subgenera, being 

 either nearly globular, or formed like a shortened e^g. 



A species of this tribe, Maia retvja, Coll. du Jard. du Roi, 

 whose shell is woolly and forms a truncated ovoid, or is obtuse 

 anteriorly; whose strongly curved elongated ocular pedicles 

 are received into fossulse situated under the lateral margin 

 of the shell ; whose carpus is elongated, as in Maia, pre- 

 sents another character which exclusively distinguishes it, viz. 

 the length of the feet seems to augment progressively from the 

 second pair onwards, or at least to differ but little. It is the 

 type of the genus 



Camposcia, Leach. 



In the others, as usual, the length of the feet progressively di- 

 minishes from the second pair to the last. 



In some of them, the ocular pedicles, although much shorter than 

 in the Stenocionops, are always salient, and the third joint of the 

 pedicle of their lateral antennae is as long, or even larger, than the 

 preceding one, the antenna; themselves terminating in a long seta- 

 ceous stem. They approach the Micippes; such is the 



Halimus, Latr.(2) 



In those which constitute the two following sub-genera, the ocular 

 pedicles are susceptible of being entirely retracted within their fos- 

 sulse, and are protected posteriorly by a dentiform projection, or 

 angle, of the lateral edges of the shell. The second joint of the pe- 

 duncle of the lateral antennas is much larger than the following 

 one; they are. terminated by a very short stem resembling an elon- 

 gated stylet. 



Hyas, Leach. 



Lateral edges of the shell dilated behind the ocular cavities which 

 are large and oval; external side of the second joint of the lateral 



(1) Cancer cervicornis, Herbst., lviii, 2, from the Isle of France. M. Desmarest 

 was mistaken inciting, as the type, Consid. Gen. sur les Crust, p. 153, the 

 Maia taurus, Lamarck. 



(2) Two species, one of which appears to be allied to the Cancer super ciliosus, 

 L., Herbst, XIV, 89. 



