160 Eev. T. A. Marshall's monograph of 



cornis, Ratz. They were taken in Mar Forest, Scot- 

 land ; and to them have been added more recently 

 others found by Mr. G. C. Champion in the Highlands. 

 A closer examination than they had previously received 

 now shows them to be Allodorus semirugosus, Nees, 

 belonging to the Sigalphides, respecting which see Trans. 

 Ent. Soc. Lond., 1885, p. 103. I can only regret that 

 they were not recognised in time to be inserted in their 

 proper place. This and other discoveries I hope to be 

 able to bring forward hereafter as a supplement at the 

 end of these papers. 



XVII. BLACIDES. 

 MaxiUary palpi 5 — 6-, labial 3 — 4-jointed. Abdomen sessile or 

 subsessile, with 8 visible segments above ; suturiform articulation 

 obsolete. Fore wings with 2 cubital areolets, the 1st separated 

 from the prsediscoidal ; radial areolet cultriform, extending nearly 

 to the apex of the wing ; radius straight ; axillary areolet not 

 divided by a transverse nervure ; recurrent nervure evected or 

 interstitial ; cubital nervure more or less obsolete ; podiscoidal 

 areolet not closed. Terebra of variable length, deflexed or straight. 



The Blacides are nearly allied to the Liophronides, 

 with which Haliday associated the first genus, Pygo- 

 stolus. The most obvious distinctions are to be found in 

 the structure of the abdomen of the females, and in the 

 wings of both sexes. In the Blacides the radius is 

 straight, and its Ist abscissa distinct, being equal in 

 length to the thickness of the stigma, or nearly so ; the 

 abdomen of the ? is never decurved at the extremity, 

 and the terebra is directed, as usual, backwards. In 

 the Liophronides the radius is curved, and its 1st abscissa 

 much shorter ; the abdomen of the ? is decurved at the 

 apex, so that the terebra points forwards. 



Nees von Esenbeck published in 1834 (Mon., i., 189) 

 a genus Blacus with two sections, but so indistinctly 

 conceived as to include in the 2d section three of the 

 Aphidiides ; while in the same work his genus Bracon 

 begins with two more Blacides, associated with two of 

 the Liophronides. The Blacus of Wesmael (1835) is 

 correctly defined, and coextensive with the present sub- 

 family. Haliday, in the same year, characterised the 

 genus Blacus, making two subgenera, Blacus and Gany- 

 chorus, and removed two aberrant species, the Ichneumon 



