GEBIA. 
CANCER (Astacus). Montagu. 
GEBIA. Leach. 
Antenne in eddem feré linea horizontali inserte : 
interiores biarticulate ; articulo primo secundo breviore : pedunculus elongatus basi 
externé dilatatus: setee due ; superiore compressa. 
exteriores triarticulate ; articulo secundo longiore: seta longissima; articulis 
subelongatis. 
Palpi pediformes 5-articulati infra pilosi. 
Pedes decem: par anticum majus zquale didactylum ; index abbreviatus : paria alia compressa 
pilosa ; ugues simplices. 
Abdomen 6-articulatum ; articulis transversis. 
Cauda pentaphylla ; processus lamelliformes lati; lateralibus costatis. 
Antenne inserted nearly in the same horizontal line: inner ones two-jointed ; the first joint 
shorter than the second; the peduncles elongate, their base externally dilated: seta two, the upper 
one compressed. External antenne three-jointed, the second joint longest; the seta very long, 
composed of subelongate joints. Pedipalpes five-jointed, hairy beneath. Legs ten; anterior 
pair largest, equal, didactyle, with the finger short: other pairs compressed, hairy ; claws 
simple. Abdomen composed of seven transverse joints. Tail with five broad lamelle; the 
lateral ones ribbed. 
All the species as indicated by the generic name, live beneath the earth, and are only to be 
obtained by digging in the mud at very low tides. 
Gebia is probably confined to the European Seas; it has been confounded with the Indian 
Genus Thalassina of Latreille, from which it differs in every character. 
