Mr. B. E. Turner on Fossorial Hymenopfera. 539 



segment more abruptly truncate and the hypopygium rather 

 more narrowly triangular. The female clitters in the much 

 greater development of the apical spine o£ the clypeus and 

 in the distinctly broader pygidium. 



I mentioned the male as a variety of H. aptenis (Proc. 

 Linn. Soo. N.S.W. xxxiii. p. 191, 1908), but this is a 

 mistake, though the structural differences in both sexes are 

 slight. H. apterus also occurs near Brisbane ; it seems to 

 show differences in the sculpture of the second abdominal 

 segment of the female in different localities, and it is 

 possible that more than one species may be confused under 

 the name, 



Thynnoides mesopleuralis^sp. n. 



2 . Nigra ; thorace segmentoque raediano rufo-ferrugineis ; man- 

 dibulis basi fusco-ferrugineis ; pedibus rufo-testaceis ; antennis 

 fuscis ; segmento dorsali secundo carinis transversis sex ; 

 pygidio angusto, elongato ; segmento ventrali qiiinto rugoso. 



c? . Niger, albo-pilosus ; mandibulis basi, cljpeo margine apicali, 

 maculaque utrinque supra basin anteimarum pallide flavis ; 

 mesopleuris rufo-ferrugineis ; tibiis femoribusque posticis subtus 

 fusco-ferrugineis ; alis hyalinis, venis nigris, stigmate testaceo. 

 Long., § 8, c? 12 mm. 



? . Head distinctly broader than long, not narrowed 

 anteriorly, rounded at the posterior angles, only slightly 

 convex, shining, the front strongly but not closely punctui'ed, 

 the vertex almost smooth, the clypeus without a carina. 

 Pronotum almost smooth, fully twice as broad as long, the 

 anterior margin broadly arched ; scutellum almost smooth ; 

 median segment closely punctured ; the whole thorax short, 

 very little longer than the head. First dorsal segment 

 punctured, broadly depressed and smooth at the apex ; 

 second dorsal segment with five transverse carinte rather 

 close together and broadly separated from the strongly raised 

 apical margin ; segments 3-5 shallowly and not very closely 

 punctured; fifth ventral segment rugose ; pygidium long 

 and very nai'row, constricted near the middle. 



cJ . Clypeus convex, very shallowly and widely emarginate 

 at the apex, closely punctured. Antennae nearly as long as 

 the thorax and median segment combined, very slightly 

 narrowed to the apex, the joints not arcuate beneath ; 

 interantennal prominence bilobed. Head, thorax, and 

 abdomen finely and closely punctured ; scutellum strongly 

 convex ; angles of the pronotum not prominent ; median 

 segment rounded. Abdominal segments strongly con- 

 stricted at the base ; seventh dorsal segment almost smooth 



