2 Mr. R. E. Turner on 
though they have been much used in description, must be 
used with extreme caution in the distinction of species, being 
far from constant, variations being very common in the 
comparative length of the second and third abscisse of 
the radius. Comparatively few Ethiopian species of the 
genus have been described, and in most of the descriptions 
important characters—such as the apical segments of the 
male, the sculpture of the second and third sternites of 
the female, and the structure of the palpi and galea—have 
not been noticed. J have not included species from Mada- 
gascar in this paper, the collection being very poor in species 
from that island. The occurrence of a species of the sub- 
genus Calotachytes in Madagascar is, however, interesting. 
The species I have not seen are marked *. 
Key to the Ethiopian Species of Tachytes. 
dd. 
1. Mandibles not excised on the outer mar- 
gin; median segment striated on the 
dorsal surface, subrectangular, the 
apical angles not rounded ; abdomen 
wholly light ferruginous red, ... Subgenus Holotachytes. 
Mandibles deeply excised on the outer [Z. dichroa, Sm. 
margin; median segment not striated 
on the dorsal surface, the apical 
angles rounded ; abdomen otherwise 
Palanrbd het sure ss eatery penne cies 2. 
2. Maxillary palpi five-jointed ; labial palpi 
three-jointed, very long and slender. Subgenus Calotachytes. 3. 
Maxillary palpi six-jointed ; ; labial palpi 
fOME pointed Pe we 's'e pier wees eee Subgenus Tachytes. 5, 
3. Four basal tergites “densely covered with 
brilliant silver pubescence ; eighth 
sternite subtruncate, the angles not 
PROGUCER-AS Sates > tacos oie Ei 7’. marshalli, Turn. 
Dorsal surface of abdomen covered with 
brilliant golden pubescence; eighth 
sternite emarginate, the angles pro- 
uced » ie savii Becton ae: eee ae 4. 
4, Seventh tergite broadly rounded; wings 
subhy aline, with a pale fuscous apical 
pand fo). Ghee eee T. mira, Kohl. 
Seventh tergite truncate at ‘the apex ; 
wings strongly INTUBEALE,. ev, Nts oa iele' T. admirabilis, Turn, 
5. Dorsal. surface’ of abdomen densely 
clothed with bright golden pube-- 
cence; head and thorax entirely with- 
out golden pabeseence*s on ee ie 6. 
Abdomen not clothed with golden pubes- 
cence, or if so clothed then with some 
golden pubescence on the thorax also. 11. 
