221 A HISTORY OF EECENT CRUSTACEA 



CHAPTER XVII 



TRIBE VII. — CARIDEA 



The respiratory system is phyllobranchiate, that is, the 

 series of branchial plumes are ' developed iti the form of 

 broad foliaceous plates of extreme tenuity, attached to a 

 central stalk.' The first two pairs of trunk-legs are fre- 

 quently but not invariably, and the last three pairs are 

 never, chelate. The ova when extruded are carried at- 

 tached to the pleopods of the female. 



This tribe contains four legions, the Crangoninea, 

 Polycarpinea, Monocarpinea, and Haplopodinea. It cor- 

 responds with the group of normal phyllobranchiate 

 Macrura of Spence Bate, to which he assigns four tribes 

 of the same extent as the four legions just named. 



Something like the Grecian bend, at one time fashion- 

 able in feminine gait and costume, is often conspicuous in 

 the species of this tribe. To this may be attributed the 

 title euhy'phota^ meaning the well-bent animals, ' applied 

 by Dr. Boas to a group in which he includes the genera 

 Pal(Bmon, Palcemonetes, Pontonia, Hippoli/te, Pandahis^ 

 Alpheus, Caridina, Crangon, Pasiphcea^ all of them members 

 of the present tribe. 



Legion 1. — Crangoninea. 



The first pair of trunk-legs is subchelate, the second 

 feeble or imperfect, with the fifth joint not subdivided. 



Family — Crangonidoe. 



This being the only family might be content with the 

 characters of the legion, but others are added for conveni- 

 ence of comparison with those in families of the next 



