BY A. RAFFRAY. 



159 



9. Metasternum leviter depressum, utrinque longitudinaliter 

 convexum. Segmentis ventralibus basalibus abbreviatis et con- 

 vexis, ultimo valde transversim biimpresso. Tibiis anticis intus 

 ante apicem leviter emarginatis. Long. 2-20-2-50 mm. 



Clarence River, Tweed River, N.S.W. (Mr. A. M. Lea). 



This fine species resembles somewhat R. insignis and R. 

 atriceps, but is larger, and its peculiar colouration leads to its 

 identification. 



It is worthy of note that in some Australian species of Rybaxis 

 the female bears on the last ventral segments impressions which 

 are generally a characteristic of the male, but at the same time 

 the ventral segments are very convex, a character which never 

 occurs in the male. R. adumbrata, both sexes of which are 

 known, proves undoubtedly that such impressions belong to the 

 female. 



Dr. Sharp (Trans. Ent. Soc. Lond. 1874, p. 496) has been 

 certainly misled by those impressions when he considers that his 

 type of optata was a male; it is certainly a female. 



Second Group 



This group includes certainly R. lunatica, King, and R. 

 electrica, King ; unfortunately I have not seen any authentic 

 specimen of these species. However, I will give the descriptions 

 of what I consider as being very likely R. lunatica and R. electrica, 

 which I found in Dr. Schaufuss' collection under those respective 

 names. I will add a new species which forms a transition 

 between the first and second groups. 



Rybaxis quinquefoveolata, n.sp. 



Oblonga, subconvexa, minus parallela, plus minusve obscure 

 ferruginea, elytris paulo dilutioribus, sat dense et longe brunneo- 

 pubescens. Caput subquadratum, quinquefoveolatum, foveis 

 tribus anticis minoribus et fronte medio declivi. Antennae validse, 

 articulis duobus primis majoribus, 3-5 subelongatis et inter se 

 aequalibus, 6 paululum breviori, 7 breviori, 8 latitudine sua tan- 

 tummodo longiori, 9 paulo majori, obconico, latitudine sua paulo 



