NEW AFRICAN BEES. 85 



large pallid spot in front ; legs black, including the tarsi ; abdomen 

 black, the hind margins of segments 2 to 4 broadly whitish, and with 

 fine silvery hair on third and fourth. 



Hah. Benguella, "found dead" (Wellman, 1474). The 

 genus Thrinchostoma was founded on a species from Madagascar ; 

 but a second species, T. productum {Halictus productus, Smith), 

 is known from Sierra Leone and the French Congo. T. pro- 

 ductum is readily known from T. ivellmani by its smaller size ; 

 the female (according to Vachal) being 8| mm., long, with the 

 anterior wing Q^ mm. Diagozoniis bicometes, Enderlein, from 

 the Cameroons, is also closely related, and it is a question 

 whether the genus Dlagozonus should be maintained. Enderlein 

 himself states that Halictus productus appears to belong to his 

 genus, apparently overlooking Thrinchostoma ; but, nevertheless, 

 there are some characters in the wing of Diagozonus which may 

 perhaps entitle it to recognition as a valid genus. 



Nomia amahilis, sp. nov. 



$ . Length nearly 14 mm., anterior wing a little over 10 ; black, 

 robust, with the pubescence partly dull white and partly black ; 

 abdomen with broad but very widely interrupted (the middle third 

 missing) light sky-blue tegumentary bands on the first four segments ; 

 scutellum prolonged into a backwardly-directed lobe on each side ; 

 postscvitellum W-like, with two prominent but obtuse angular projec- 

 tions. Head broad, with much white hair ; clypeus dull, striatulate- 

 granular, with a faint rather shining median ridge ; antennse dark, 

 but the fifth joint orange-ferruginous beneath ; flagellum rather 

 thick ; mesothorax dull and densely punctured, with black hair, 

 except at the sides ; pleura, tubercles and sides of metathorax with 

 copious white hair ; tegulae large, black ; wings very dark, nervures 

 and stigma black ; legs black, with the hair partly black and partly 

 white, but orange-ferruginous on inner side of basitarsi, especially 

 the last ; hind tibiaB with the hair black on outer and yellowish-white 

 on posterior face ; middle tibiae with the hair of basal half of outer 

 face mostly white, and of apical half mostly black ; anterior tibiae 

 with the black confined to the apical fourth ; abdomen above with 

 scanty black hair; fifth segment covered with orange-ferruginous 

 hair, with some black bristles overlapping ; apex with black hair. 



Hah. Benguella, "flying near a house" (Wellman, 1469). 

 This agrees in the structure of the scutellum and postscutellum 

 with N. scutellaris, Sauss., from Madagascar; but differs by the 

 very dark wings, and the beautiful blue markings of the abdomen. 

 Friese has described two forms of the sciitellaris-gvon^ from the 

 African mainland : N. maculata (Friese) and iV. nigripes (Friese). 

 These differ from N. amahilis in having the abdominal markings 

 reduced to quadrate spots on each side, of a bluish-white colour ; 

 while the wings are only moderately dark, as in scutellaris. From 

 the blue markings on the abdomen, N. amahilis looks at first 

 sight like a Crocisa. 



