100 



the type appears from the description to have been a male, but 

 my specimen agrees with Gestro's figure of the female); the other 

 two are not unlikely to be two of intermedia, Gestro, titaiium^ 

 Thorns., and poUtulum, MacL, but I cannot identify them confi- 

 fidently. I have also before me two species from Central and 

 one from Western Australia which are all certainly undescribed, 

 and of which I furnish descriptions below. I also furnish, below, 

 a tabulation showing the prominent characters of all the species 

 of this section of the genus (except intermedium, titanum, and 

 politulum, which J am quite confident are not identical with any 

 of the species characterised in the tabulation, but which I am not 

 able to tabulate from the descriptions). 



In this genus the form of the ligula is very diverse, but appears 

 to be constant in individuals of the same species ; at any rate it 

 is constant in specimens of G. longipenne, Germ., — the only 

 Gigadeina of which I have been able to examine a fairly long 

 series, — and also in such few specimens as I have seen of other 

 species. The form and proportions of the prothorax al^o furnish 

 reliable specific characters so long as the fact is allowed for that 

 in nearly (if not quite) all the species the front outline of that 

 segment presents sexual characters. Further valuable assistance 

 in the identification of species may be found in the puncturation 

 of the elytra, which (so far as I can judge) is but little affected 

 by sex. The sexes in this genus are not very readily determined 

 by external characters ; I do not find any constant sexual 

 character on the ventral segments, and the anterior tarsi are 

 scarcely dilated in the males ; in some specimens however the 

 front tarsi bear some sucker-like papillae on their under surface, 

 and I have assumed this to be a male character. 



G. dux, sp. nov. Mas. Robustum ; nigrum ; capite insequali, sparsim 

 irregulariter sat fortiter punctulato ; ligula pernitida punc- 

 turis paucis impressa, in parte mediana depressa, ad latera 

 elevata (antice obtuse, postice sat anguste) ; prothorace 

 quam longiori ut 10 ad 6 latiori, fere ut G. longipenne, Germ, 

 maris conformato (i.e. laterum arcu, margine antico, et 

 angulis similibus) sed lateribus ad basin magis parallelis 

 (his in parte dimidia postica obtuse crenulatis), disco toto 

 fortiter crebre transversim strigato ; elytris striatis, inter- 

 stitiis sat planis (7'' nullo modo cariniformi) creberrime nee 

 seriatim rugulosis (sed apicem versus interstitiorum externo- 

 rum puncturae nonnihil biseriatim impressse apparent). 

 Long., 17 1.; lat., 5| 1. 



A very large and deep black species. The non-seriate sculpture 

 of its elytra! interstices (except in the apical portion near the 

 lateral margins) and the very strong close transverse wrinkling 



