GALATHEA. 
CANCER. Linn ., Gmel. 
ASTACUS. Johns t.^ De Geer , Pennant . 
G ALATHEA. Fabricii , DaldorJ, \ Lamarck , Latreille , ImcA. 
Antenna: exteriores corpore longiores segmentis basilaribus tribus crassioribus, secundo baud 
longiore quam latiore; 
Interior es pedunculo elongat o infra oculos insert® segmento ultimo acuto multiarticulato 
infra ciliato, set$ articulata ad basin. 
Pcdipalpi gemini externi 5-articu!ati, articulo prime interne baud dilatato. 
Pedes decern; par anticum sequale, crassius, didactylum indice ad apicem saltern dentato; paria 
2, 3, et4 simplicia consimilia, subcompressa, unguibus acutis instructa; par quintum brevius 
spurium articulo ultimo inermi, ciliato. 
Abdomen 6-articulatum. 
Cmidci pcntaphylla ; processibus medio fixo e segmentis composite, duobus externis simplicibus 
mobilibus. 
GENERIS DIYISIONES. 
Rostrum acuminatum acutum utrinque 4 -sptnosum ( spina, postied minore). Pedes antici compressi. 
Abdomen segmentis lateraliter obtusis. Cauda lamella intermedia triangidari apice emarginato 
laciniis apice rotundatis. 
a. Antenna tnteriores 4- articulata articulo primo apice unispinoso, pedunculo apice bispinoso. 
Pcdipalpi gemini externi caiiti interno articulo secundo primo longiore. 
b. Antenna interiores 3-articulata, pedunculo trispinoso. Pcdipalpi gemini externi cauli interno 
articulo primo secundo longiore. 
** Rostrum elongatum spiniforme basi utrinque bispinoso ( spina postied minore ). Pedes antici 
subcjlindrici . Abdomen segmentis lateraliter acutis. Cauda lamella intermedia transverso- 
quadrata apice subemarginato . 
(Antenna interiores triartic.ulata , pedunculS 3-spinosti. Pedipalpi gemini externi cauli interno 
articulo primo secundo longiore.) 
External antennas longer than the body, with the three first segments thicker than the others, 
the second not longer than broad ; internal antennas with an elongate footstalk inserted beneath the 
eyes, their last joint acute composed of many segments, ciliated beneath, with ai^articulated seta 
at its base. External double feet-palpes five-jointed, the first joint not dilated internally. Legs 
ten ; anterior pair didactyle, equal in size and thicker than the other legs ; second, third, and fourth 
pairs simple, alike in form, somewhat compressed, with acute nails; fifth pair shorter, spurious, 
the last joint simple ciliated. Abdomen six jointed; tail composed of five foliaceous processes, 
the middle one of which is fixed and composed of several pieces, the outer ones being moveable. 
