British Hymenoptera. 203 



with brighter brown; wings slightly dusky, and with a rather 

 darker apical margin. Abdomen rather shining, punctured, seg- 

 ments deeply impressed across the base ; 1st and 2nd segments 

 clothed with pale hairs, the rest clothed with black hairs at the 

 base, but with an apical fringe on each side of pale brown hairs ; 

 apical crest of 6th segment very slightly emarginate ; 7th with a 

 triangular apical tubercle ; beneath clothed with pale hairs ; 5th 

 segment shining, with a semicircular hairy patch in the middle of 

 the apical margin ; 6th very narrow, with scarcely any apical 

 wing, and with the surface above the apex clothed with long simple 

 hairs laterally adpressed (for genitaha, &c., see PI. IX., figs. 5— 5 a). 

 Legs clothed with pale hairs. 



2 . With the mandibles largely and rugosely punctured, only 

 slightly flattened in front. Thorax clothed as in the ^ , but rather 

 less densely, and with the hairs rather shorter. Abdomen rather 

 strongly punctured ; the base of the 2nd and 3rd segments deeply 

 and narrowly impressed, the 1st and 2ud segments clothed with 

 pale ochreous hairs ; the remainder with short black hairs, upright 

 on the apical as well as on the other segments ; each segment with 

 a narrow line of pale hairs on each side of the apex ; scopa of the 

 ventral segments bright orange. Legs clothed with pale hairs. 

 Length, 10 — 12 mm. 



Hah. The commonest species of the genus, and gene- 

 rally distributed. 



7. Megachile argentata, Fab. (PL IX., figs. 7 — 7 a). 



Fab., Ent. Syst., ii., p. 336 ; Smith, Cat. Brit. Hym., 

 2nd ed., p. 176. 



Smaller than any of the preceding, black, clothed with ochreous- 

 grey hairs ; g- with the anterior tarsi simple, and the 6th segment 

 of the abdomen densely clothed with adpressed whitish hairs, 

 except a triangular spot at the apex ; apical carina denticulate ; j 

 with the ventral scopa silvery grey. 



3" • Head and thorax closely punctured, the former broader or 

 as broad as the latter ; face densely clothed with silky golden grey 

 hairs ; mandibles shortly grooved at the apex, rugose and hairy at 

 the base. Antennae reaching to the scutellum, with the apical joint 

 flattened, but scarcely dilated. Thorax densely clothed round its 

 margins with ochreous-grey hairs, very closely punctured ; wings 

 shghtly clouded. Abdomen finely punctured ; 1st, 2nd, and 3rd 

 segments densely clothed with rather long ochreous-grey hairs ; 

 4th with shorter ones intermixed with black ; 5th with black ones 

 pn its apical half ; the 2nd, 3rd, and 4th with an apical fringe of 



