BY T G. SLOANE. 581 



character in the tribe. The biseriate disposition of the punc- 

 tures seems to have originated on the odd interstices, spread- 

 ing backwards from the base (in Neohelluo with triseriate 

 interstices, the punctures become biseriate just before the apex 

 on the second, third, and fourth interstices). The eighth inter- 

 stice has remained pluripunctate in more cases than any other 

 interstice, and here a tendency to loss of punctures is a recent 

 character, but no proof of affinity (e.g., it occurs in South 

 American species of Ilelluomoryhd^ and in the Australian 

 Ametroglossus niger; a large species ticketed Helluomor'pha 

 (jagates Chaud., in the Ehlers collection, has the second, 

 fourth, and sixth interstices impunctate, the fifth and seventh 

 uniseriately punctate near stria on outer side). The unusual- 

 ly narrow, ninth interstice, in comparison with the wide 

 eighth, is characteristic of the small Australian section includ- 

 ing Gigadema, Neohelluo, ^Enigma, and Ametroglossus. Pro- 

 sternum : this varies in convexity (depressed in Epimicodema 

 and Ame\troglossus, convex in jEnigm-a). Sometimes there is 

 a transverse sulcus along the anterior margin (e.g., Gigade- 

 ma), but sometimes this is wanting (e.g., Ametroglossus). 

 The intercoxal declivity varies ; it is strongly declivous in 

 Helluo and Helluapterus, more gently so in Gigadema nocte 

 and Helluarchus; sometimes it ends in a flattened flange 

 against the peduncle, sometimes the flange is wanting (e.g., 

 Helluarchus). Legs: there are varying forms of the anterior 

 tibiae; {a) stout, wide at apex, inner notch deep, upper spine 

 at about one-half the length of the tibia, often nearer base 

 than apex (type, Helluo) ; (h) long, narrow, with inner notch 

 shallow and much nearer apex (type, Gigadema). In Hellu- 

 archus, Helluapterus, JUJnignia, and Ametroglossus, the ante- 

 rior tibiae incline towards the form found in Gigadema, which 

 i-? more recent than the form found in Helluo. 



Characters peculiar to the Australian group. 

 Head with one sensitive hair on each side. Antenna' with 

 fourth joint long, sparsely setose (e.g., Gigadema). Clypeus 

 emabrginsitG [Helluonidius and Dicranoglossus). Lnhrnm bisetose: 



