PROCESSA. 
Antenna r superior es breviores setis duabas in eadem, fere linea horizontali insert is, seta interiore 
longiore : pedunculus 3-articulatus articulo primo longiore; ultimo breviore. 
Inf eriores corpore longiores, setaceas deerescentes, squama ad apicem externe unidentatd 
pedunculo annexa. 
Palpi pcdiformes articulis quatuor ex sort is, secundo longissimo ad basin interne subabrupte 
emarginato 
Pedes decern; par anticum pede uno didactylci, alterO monodactylo; par secundum inequale, 
didactyl um tenue, hoc longissimo carpo cubitdque multi-articulatis, illo breviore carpS 
multi-articulato : paria tertium, quartum et quintum unguibus acutis, simplicibus instructa. 
Abdomen 6-articulatum, segmento secundo infra antice et postice producto. 
Cauda pentaphylla; processibus externis bipartitis parte exteriore mobili. 
Superior antennae shortest, with two setae placed in nearly the same horizontal line; the 
interior seta largest: peduncle with three joints, the first of which is the largest, the third the 
shortest: inferior antennae setaceous and larger than the body, furnished at their base with a 
large scale, having its external point unidentate. Pediform palpi with four exserted joints; 
the second joint very long, somewhat abruptly emarginate at its base internally. Legs ten; 
anterior pair with one leg didactyle, the other monodactyle ; second pair unequal, one being 
very long, having its wrist and fore-arm composed of many joints, the other having the 
wrist only jointed . thiid, fourth, and fifth pair furnished with sharp simple claws. Abdomen 
six-jointed, the second segment beneath anteriorly and posteriorly produced. Tail composed of 
five plates; the external plate composed of two parts, separated by a hinge-joint. 
The discovery of the species constituting this most curious and interesting genus, is the 
result of Montagu’s indefatigable labors. The circumstance of the legs on different sides of 
the same animal being different in length is not an uncommon occurrence in several crustaceous 
genera, but this is the first instance in which the legs of opposite sides have been found to differ 
in essential structure. 
