580 REVISIONAL NOTES ON AUSTRALIAN CARABIDiE, V., 



In Australian genera (all have been dissected by me except 

 Helluapterus and Helluarchus), it is only possible to observe 

 the paraglossae with accuracy from the inner side of the 

 labium ; in all our genera they are very rudimentary, in some 

 being reduced merely to the lateral parts of the cartilaginous 

 basal support of the ligula (e.g. Helluosoma and Helluo). In 

 Omfhra (the only foreign genus examined by me), the narrow, 

 cartilaginous paraglossae may be seen attached to the sides of 

 the wide ligula, their point being free and not extending to 

 the apical angle of the ligula. 



Maa-Ulct : the cardo is triangularly prominent at the exter- 

 nal angle in Gigadema ^naxillare cT ', ^ slight tendency to this 

 form is noticeable in Neohelluo angulicollis ; inner lobe of 

 variable form. It is of ordinary form in most genera (e.g. 

 Helluo), but the following are variations, {a) apex carried 

 forward beyond the apical hook (the hook set almost at right 

 angles to the galea, e.g., Helluodema and Neohelluo); (h) 

 apex with a tuft of hair (e.g., Ametroglossus and Neohelluo) ; 

 {c) galea triangularly protuberant in middle [Gigadema (ex- 

 cept G. longipenne), H ellua'pt erus , and Helluarchus] ; the 

 outer lobe is of variable shape, in Dicranoglossus long, slen- 

 der, and glabrous, in Gigadema stout, and setose. Prothorax : 

 the form varies ; in Neohelluo, the anterior angles are marked ; 

 in Gigadema grande, the anterior margin is prominent in the 

 middle (especially in cT) ; the distance of the basal angles 

 from the peduncle varies, in Gigadema near the peduncle, in 

 ^■Enigma distant from it ; the base is truncate in HeUua'pterus 

 and Helluarchus (angles not near peduncle), but slopes for- 

 ward to the basal angles on each side of the peduncle in 

 Helluo. The anterior and basal margins are fringed with hair ; 

 sometimes the fringing hairs are wanting on the lower part of 

 the base, sometimes present (e.g., Gigadema, Helluo). Elytra: 

 the stem, from which the Helluonini are derived, evidently 

 had the interstices of the elytra closely setigero-punctate ; but 

 a tendency for these punctures to be reduced to two rows, on 

 some of the interstices, must have appeared as a very early 



