g98 CRUSTACEA. 



Plate 61, fig. 3 a, animal, enlarged ; b, leg of sixth pair. 



Rio Janeiro. Collected, January 4, 1839. 



Length, six to seven lines. Colour, green, shaded with olive-green 

 and yellow ; posterior legs in third and fourth joints, partly carmine. 



The reniform eye of this species leads me to doubt the correctness 

 of arranging it with the Allorchestes ; and as I made no dissection, 

 I am not sure that its mandible has no palpus, or that its posterior 

 stylets are simple. The head is a little longer than the next seg- 

 ment. The last two basal joints of the inferior antennae are sub- 

 equal. The fiagellum of this pair rather stout ; of the superior quite 

 slender. 



The claw of the anterior feet is rather longer, and closes against a 

 considerable part of the lower margin of the hand or preceding joint. 

 The same remark applies to the finger of the next pair ; when closed 

 it points towards the base of the hand; the palm has a few minute setae; 

 the hand is about twice as long as its breadth. 



The first pair of stylets extends farther back than the second, and the 

 third pair is very short. The branchiae are narrow oblong; they are 

 attached to the bases of all the legs excepting the first and last pairs. 



Allorchestes? graminea, Dana, Proc. Amer. Acad. Sci., ii. 208. 



Allorchestes media. 



EpimercB magnce. Antenna lmce dimidio 2darum longiores, flagetto 

 14:-articidato, articulis paree oblongis, setis partim divaricatis et perbre- 

 vibus, partim infra stride appressis et brevibus; 2dm dimidio corporis 

 breviores, flagello longiore quam basis, lti-articidato, articulis parce 

 oblongis, setis numerosis et verticillatis proeter in latere externo nudo, 

 latitudine articidorum non longioribus. Pedes a.ntici parvuli, manu 

 obkmgd, mar ginibus fere parallelis, infra partim 7iirsutis, apice oblique 

 trwicatis, digito brevi, carpo infra rotimdato et pilis ornato. Pedes 

 2di pervalidi, manu subovatd, supra arcuatd r palmd multo oblique 

 transversd, spinulosd, versus digiti basin paido elevatd, digito dimidio 

 manus parce longiore, carpo inter manum articulumque Stium infra 

 non producto, articido alio antice triangulato, fere acuto. Pedes bti 

 Qti 7 mi sat breves, subwqui, semim increscentes, setis paucis, articulo bto 



