GALATHEA. 
CANCER... ZLinn., Gmeil. 
ASTACUS. Johnst., De Geer, Pennant. 
GALATHEA. Fabdricii, Daldorf, Lamarck, Bosc, Latreille, Leach. 
Antenne exteriores corpore longiores segmentis basilaribus tribus crassioribus, secundo haud 
longiore quam latiore ; 
Interiores pedunculo elongato infra oculos inserte segmento ultimo acuto multiarticulato 
infra ciliato, seta articulata ad basin. 
Pedipalpi gemini externi 5-articulati, articulo primo interne haud dilatato. 
Pedes decem; par anticum «quale, crassius, didactylum indice ad apicem saltem dentato ; paria 
2, 3, et & simplicia consimilia, subcompressa, unguibus acutis instructa ; par quintum brevius 
spurium articulo ultimo inermi, ciliato. 
Abdomen 6-articulatum. 
Cauda pentaphylla; processibus medio fixo e segmentis composito, duobus externis simplicibus 
mobilibus. 
GENERIS DIVISIONES. 
* Rostrum acuminatum acutum utrinque 4-spinosum (spind posticé minore). Pedes antici compressi. 
Abdomen segmentis lateraliter obtusis. Cauda lamella intermedia triangulari apice emarginato 
laciniis apice rotundatis. 
a. Antenne interiores 4-articulate articulo primo apice unispinoso, pedunculo apice bispinoso. 
Pedipalpi gemini externi cauli interno articulo secundo primo longiore. 
b. Antenne interiores 3-articulate, pedunculo trispinoso. Pedipalpi gemini externi cauli interno 
articulo primo secundo longiore. 
** Rostrum elongatum spiniforme basi utrinque bispinoso (spiné posticad minore). Pedes antici 
subcylindrici. Abdomen segmentis lateraliter acutis. Cauda lamella intermedia transverso- 
quadrata apice subemarginaté. 
(Antenne interiores triarticulate, pedunculé 3-spinosé6. Pedipalpi gemini externi cauli interno 
articulo primo secundo longiore. ) 
External antenne longer than the body, with the three first segments thicker than the others, 
the second not longer than broad ; internal antenne with an elongate footstalk inserted beneath the 
eyes, their last joint acute composed of many segments, ciliated beneath, with an articulated seta 
at its base. External double feet-palpes five-jointed, the first joint not diated 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. 
