290 MR. R. E. TURNER ON THE [Feb. 15, 



Allied to melleus Westw. and also to insidiator Sm. and agilis 

 Sm., from the last of which the male is hardly distinguishable by 

 any constant character, though the size is different. But the 

 female has the head somewhat broader than in agilis, the pygidium 

 narrower, and the sculpture different. In the male the yellow 

 marks on the abdomen are less extensive than in agilis, the spot 

 on the mesonotum is more developed, being often entirely absent 

 in agilis, and the angles at the base of the hypopygium are some- 

 what less prominent in the present species. 



Elidothynnus basalis Sm. 



Thynnus basalis Sm. Cat. Hym. B. M. vii. p. 23 (1859), <3 . 



A long series of this species and of T. tubercidifrons Sm. sent 

 by Mr. Giles, who states that they are two of the commonest 

 species in the neighbour-hood of Perth and that the females seem 

 to him to be identical. The females sent are similar to that 

 previously described by me from a damaged specimen as the female 

 of T. ttiberculifrons Sm., but the low carina on the pronotum is 

 absent. I am therefore driven to the conclusion that the speci- 

 mens with the red abdomen (basalis) and those Avith the black 

 abdomen {tubercidifrons) are two forms of the same species distinct 

 from vastator Sm., though intermediate colour- varieties do not 

 seem to occur. One specimen, apparently identical with basalis, 

 is, however, paired with a female closely resembling that described 

 by Smith as vastator, though differing in the presence of four- 

 raised carina? instead of three at the base of the second dorsal 

 segment. I have dissected out the genitalia of basalis and tuber- 

 culifrons, and can find absolutely no difference. 



Lestricothynnus constrictus Sm. 



Thynnus constrictus Sm. Cat. Hym. B. M. vii. p. 19 (1859), <3 . 



$ . Clypeus with an obscure carina at the base, the anterior 

 margin feebly and very broadly rounded ; mandibles stout and 

 rather short. Head moderately convex, rather large, nearly as 

 long as broad, rounded at the posterior angles, shining, very 

 sparsely and shallowly punctured, with a short, longitudinal, frontal 

 sulcus ; three large punctures in a triangle on the vertex. Thorax 

 very finely and sparsely punctured, a row of deeper punctures each 

 bearing a seta along the anterior margin of the pronotum, which 

 is narrower than the head, nearly rectangular and almost twice 

 as broad as long. Median segment a little longer than the 

 scutellum, broadened from the base and abruptly truncate 

 posteriorly, deeply and rather closely punctured, the surface of 

 the truncation almost smooth. Abdomen very sparsely and finely 

 punctured, the first segment with the apical margin raised and a 

 deep transverse groove before it ; the second segment with about 

 eight transverse carina? including the raised apical margin, the six 

 basal carina? low and more or less irregular, the two apical carina? 

 higher and regular; fifth segment more closely punctured. 



