19 Mr. R. E. Turner on 
Subgenus Holotachytes, subgen. nov. 
Differs from typical Tachytes in the absence of the 
incision on the outer margin of the mandibles, in the 
striation of the dorsal surface of the median segment, and also 
in the longer and more rectangular shape of that segment. 
Type of the subgenus, Tachytes dichroa, Sm. 
Unlike Calotachytes this subgenus has the galea short and 
broadly rounded at the apex, “not rostrate ; ; and the joints 
of the labial palpi are short and stout. 
1. Tachytes (Holotachytes) dichroa, Sm. 
Tachytes dichroa, 8m. Cat. Hym. B.M. iv. p. 299 (1856). ¢. 
Larrada ferox, Sm. Ann, & Mag. Nat. Hist. (4) xii. p. 294 (1878). 9. 
Hab, Gambia (type ¢); N. Nigeria, Oye River near 
Lajollo (J. W. Scott-Macfie) ; Gold Coast, N. Territories, 
Wa (J. J. Simpson), May. 
Subgenus Calotachytes, subgen. nov. 
The three following species—T. marshalli, Turn., T. mira, 
Kohl, and 7. admirabilis, Turn.—form a section of the genus 
structurally distinguished by the five-jointed maxillary and 
three-jointed labial palpi, other species of the geuus having 
six-jomted maxillary and four-jomted labial palpi. The 
basal joint of the labial palpi is extremely long and slender, 
much longer than the second joint of the flagellum, and the 
galea is very elongate. These two characters, however, are 
also present in 7. observabilis, Kohl, velox, Sm., and other 
related species. I look on the difference in the number of 
the joints in the palpi as of subgeneric importance. The 
known species are confined to the Ethiopian region and are 
of large size, and have at least the four basal dorsal seg- 
ments. densely covered with golden or silver pubescence. 
The second sternite of the female is shining, with large 
sparse punctures. 
Type of the subgenus, Tachytes marshall, Turn. 
In addition to the three Ethiopian species noticed below, 
T’. argyropis, Sauss., from Madagascar, also belongs to the 
subgenus. 
2. Tachytes (Calotachytes) marshalli, Turn, 
Tachytes marshal, Turn, Ann. & Mag. Nat. Hist. (8) ix. p. 420 
(1912). Qo. 
Hab. Mashonaland, Salisbury (G. A. K. Marshall) ; 
