151 
IBACUS,. 
CHARACTER GENERICUS, 
Testa latior quam longa, subdepressa, utrinque profundis- 
simé incisa: ocu/i in margine anteriore inserti: peduncue 
lus crassus, recurvus, apicem versus acuminatus. 
Pedipalpi externi articulis duobus primis externé cristatis : 
articulo secundo interné mult6-fisso: flagrum triparti- 
tum; segmento ultimo multi-articulato. 
Pedes decem, breves: paria duo antica aliis abrupté cras- 
siora: par quintum didactylum ; pollice abbreviato. 
Cauda pentaphylla; lamellis membranaceis, basi crustaceis. 
Antenne interiores 3-articulate, setis duabus articulatis ter- 
minatz. 
exteriores squamiformes, 4-articulate. 
el 
IBACUS. 
GENERIC CHARACTER. 
®hell broader than long, subdepressed, on each side very 
deeply fissured; eyes inserted at the anterior margin; 
peduncle thick, recurved, acuminated towards its extre- 
mity. 
External pedipalpes with the two first joints externally 
crested ; second joint internally, with many fissures: 
flagrum tripartite ; the last serment many -jointed. 
Legs ten, short; two anterior pair abruptly thicker than the 
others; fifth pair pair didactyle ; thumb short. 
Tail with five membranaceous lamella, which are crusta- 
ceous at their base, 
