MATA. 
MAI A, Aristotelis. 
MAIA, Lamarck, Latreille, Bosc, Leach. 
CANCER, Olivier, Scopoli, Herbst. Sowerby. 
Antenne externe setaceex, articulis duobus basilaribus crassioribus et longitudine subaqualibus ; 
articulo primo subcrassiore. 
Pedipalpi externi caulis interni articulo secundo ad apicem internum profundé emarginato, 
Pedum par anticum aliis haud aut vix crassiores: paria octo postica subelongata consimilia, 
unguibus simplicibus apice nudis, acutis. 
Abdomen 7-articulatum. 
Testa connexa ovato-subtriangularis, spinosissima, anticé rostro bifurco terminata. 
Ocult pedunculo suo elongato haud crassiores. 
External antennz setaceous with the two first joints thickest and nearly equal in length ; the 
first joint thickest. External pedipalpes with the second joint of their internal footstalk deeply 
notched at its internal apex. Anterior pair of legs not or scarcely thicker than the rest: the 
other legs alike in form, subelongate: the claws simple, with their joints sharp and naked. 
Abdomen seven-jointed. Shell convex, ovate-subtriangular, very spinose, terminated anteriorly 
by abifurcate rostrum. Eyes not thicker than their peduncles which are elongate. 
