356 0^ THE AUSTRALIAN BEMBIDllDES, 



The principal features used in the synoptic table of species 

 which follows seem to divide the species here placed in Taclujs 

 into distinctive groups that are readily separated from one 

 another; indeed the most important of these groups are apparently 

 so distinct that they might be removed from Tachys altogether 

 and formed into separate genera; but to do this would require a 

 fuller knowledge than I possess of the genera now regarded as 

 capable of maintenance among the Subulipalpi, and of the system 

 adopted in classifying them. The minor features used in the table 

 for separating closely allied species from one another are not 

 perhaps always the best that could have been chosen, though they 

 have seemed to me to be so. 



The following species of Tachijs, described by the Rev. Thos. 

 Blackburn, are unknown to me in nature, and, for that reason, 

 have not been included in the table, viz., T. haldiensis, T. 

 hifuffcatits, and 7'. adelaiike. 



Genus Tachys. 



Owing to the variable number of stri;« on the elytra among the 

 species of the genus 7'ac/ti/s (the full number is eight strife and a 

 marginal channel, but this only occurs in 7\ yarrensis, Blkb., 

 among the species known to me) the ordinal number to indicate 

 the stria next the marginal channel would var}^, and as this stria 

 seems a feature of great classificatory importance it becomes 

 needful to use an unvarying term for it. I therefore call it the 

 suhmarginal stria. The interstice between the submarginal stria 

 and the marginal channel I call the lateral iiiterstice. 



Table of Species known to me. 

 I. Elytra with sulunarginal stria well marked. 

 A. Prothorax with a submarginal lateral carina 

 near base. 

 h. Upper surface shagreened and finely 



punctulate (uuicolorous) T. Jtrinutipennis, Macl. 



hb. Upper surface shagreened, impunctate 



(bicolorous) T. ectromioides, SI. 



AA. Prothorax without a submarginal lateral 

 carina near base. 



