56 SYRPHIDJS. 



pentaspila are synonyms corresponding to the two usual forms of 

 the male and female. To these three species is to be added Paragus 

 signatus. Walker, from Durban, and perhaps also Microdon varius, 

 Walker, from fcierra Leone. From the Oriental Kegion no less than 

 nineteen species have been described by Osten Sacken, Brunetti and 

 de Meijere. The genus seems therefore to be mainly Oriental, but 

 Africa possesses some very interesting species, provided with very 

 peculiar structural characters. All these species seem to mimic the 

 hymenopterous genus Melipona, which they resemble very much 

 in shape, colouring, and structure of the legs ; probably they are 

 scavengers in their habits, as are our species of Volucella. 

 In the collection there are the four following species : 



1 (2) Second and fourth longitudinal veins bearing 



from the base to the middle very numerous 

 and long bristles ; basal joint of middle 

 tarsi in the male not dilated and as long 

 as the four succeeding joints; scutellum 

 with a yellow margin and a broad black 

 depression ; legs with black markings ; 

 wings with three narrow dark bands. . . . triangulifera, Big. 



2 (1) The second vein alone with bristles near 



the base ; species usually of larger size ; 

 wings with broad brown spots or bunds. 



3 (4) Legs usually of a pale yellow colour, with- 



out any black marking; scutellum with 

 a very broad black depression, apparently 

 black with a yellow border; abdomen 

 yellow, with black markings; basal joint 

 of middle tarsi MS long as the others taken 

 together ' xanthopoda, sp. n. 



4 (3) Legs with black markings on the femora 



and tibiae; pcutellum yellow, with a 

 small central black depression ; basal 

 joint of middle tarsi short, and that of 

 the male dilated, only as long as the 

 next joint; abdomen black, with yellow 

 markings. 



5 (6) Scutellum entirely of a reddish colour, the 



median depression alone black ; thorax 

 and abdomen with golden tomentuin and 

 golden hairs aurea, sp. n. 



6 (5) Scutellum yellow, with the basal half 



black ; thorax without golden tomentum 



or golden hairs nigra, sp. n. 



50. Graptomyza triangulifera, Bigot (1882). 



A small species, readily recognised by the fourth longitudinal 

 vein being bristly towards the base and by the peculiar abdominal 

 pattern. 



The male measures 5-6 mm. in length and was described by me 

 as melanura ; the female measures 6-7 mm., and was described by 

 me as pentaspila. I am enabled to substantiate this synonymy 



