ZOOLOGICAL AND BOTANICAL ASSOCIATION. 191 



Abdominis coxis ut genus. Telson (eing. ult) triangulare; lateribus 

 txcivatis, superne sub-sulcato ; setis tuberculisque marginato. 



Habitat : in formicariis ad " Lulworth Cove, Sussex," Anglia, 

 Rev. A. R. Hogan. Et Gallia in formicariis ad Fontainbleau, Paris, 

 M. H. Lucas. 



Platyabthbtjs {Brandt). 



Body flattened ; head transverse ; lateral and rontal lobes strongly 

 marked, arising from frontal margin, which passes deeply down into the 

 third ring. Third ring reduced to a small triangular plate on each 

 side. 



Internal antennte three-jointed. 



External antenna) : peduncle five (5) jointed, second joint slightly 

 lobed internally, fifth broad and flattened. Tige two-jointed, rounded, 

 scabrous. 



Cephalothorax : coxae well developed, somewhat squared. Ab- 

 domen : coxae of first and second somites obsolete ; coxae of third, 

 fourth, and fifth well developed, curved downwards. Telson (last 

 somite) : coxae obsolete. 



Posterior pleopods (false feet) attached to superior external lateral 

 angle of ventral portion of telson, which is incomplete beneath. Pe- 

 duncle (basis) nearly completely uncovered, sub-rotund (?), sides parallel. 

 Accessory lobe well marked, soldered to peduncle for two-thirds of its 

 length. Accessory filaments well marked, slender. Ischium flattened, 

 trigonal, terminating in a filament. Species, PI. Hoffmannseggii. 



Species 1 — Plathyarihrw Hoffmannseggii {Brandt), 



Body scabrous, covered with compressed, scale-like, club-shaped 

 prominences. The posterior margins of the cephalothoracic and abdo- 

 minal somites edged with similar prominences, so as to appear crenu- 

 lated ; on the lateral borders of the coxae these become converted into 

 curved bristle-like hairs, best marked on the abdominal somite. 



Head densely scabrous, somewhat triangular, deeply embedded in 

 the fifth ring of the cephalothorax, arched in front Lateral lobes pro- 

 minent Frontal lobe continuous across forehead, arcuate, fringed with 

 coarse hairs. Internal antennae inconspicuous. External antennae 

 densely scabrous. Peduncle : 1st joint short ; 2nd, with a small lobe on 



ZOOL. A BOT. SOC. PBOC VOL. I. 2 D 



