The Odonata or Dragonflie* of South Africa. 409 



DIPLACODES (Kirby, 1899). 



A genus embracing a small number of species, but several of them 

 very widely distributed in tropical and sub-tropical Africa, Asia, and 

 Australia, and common where they occur ; a parallel to the American 

 genus Erythroiliplax, although not equal to this one in importance for 

 the respective faunal region. 



Smaller species. Adult males with labium, face and frons whitish yellow, 

 a broad basal black band of frons. Thorax prinnose blue, elliptical 

 ante-humeral spots indicated by lighter colour of pruinosity. Abdomen 

 black with segments 1 -3 pruinose blue. Wings hyaline with very small 

 brownish spot at base of second pair ; only one or two cells at membranule. 

 Females and immature males black and light yellow, much like the 

 following species. $ , Aid. 18, hdw. 20, pi. < 2 mm, ?, 13'5, 16, < 2 



to 15, 19, < 2 D. exilis. 



Larger species, but very variable in size. Adult males wholly black, 

 ventral surface of thorax and abdomen very slightly whitish pruinose. 

 Wings mostly with a diffuse greyish cloud at tips ; basal spot of second 

 pair brown to Cuq or slightly beyond and to end of membranule ; 

 pterostigma greyish' ochreous to dark ferruginous. Immature males 

 gradually passing from a black and yellow pattern similar to female to 

 the mature colour. Females with lips, face and frons light yellow ; 

 black basal line on frons. Thorax light yellow with blackish markings ; 

 line near median suture ; broader line on humeral suture and an oblique 

 band between ventral third of humeral and dorsal end of ante-humeral 

 line; line between humeral siiture and metastigma dorsally incomplete ; 

 at metastigma ventrally incomplete on second lateral suture ; on met- 

 epimeron dorsally incomplete (this pattern gradually developing from an 

 almost unmarked condition). Abdomen light yellow with mid-dorsal 

 black band on segments 1-10, latero-ventral black bands on segments 

 3-10; lateral bands mostly broader on posterior half of each segment 

 and fused to dorsal band by a small terminal dilatation of the latter on 

 segments 6-10. Wings hyaline, no terminal greyish cloud ; basal spot in 

 posterior pair similar in extent to male, but deep golden yellow ; ptero- 

 stigma light yellowish ochreous. J . Abd. 17, hdw 19, pt. 2 mm. to 25, 

 29, 3'5. J , 17, 23, 2'5 to 20, 23, 3 ... . D. Lefebvrei. 



"DlPLACODES EXILIS (ElS, 1911). 



Coll. E. B. Williamson : 1 $ , Salisbury, Mashonalaud (ix . 1900, 

 Marshall). 



The present specimen is the only one known to the writer from 

 continental Africa ; the type series came from Madagascar. Although 

 mature males are widely different from D. Lefebvrei in similar 

 condition, looking much like a minute edition of the Asiatic D. 

 trivialis, immature males and females are not easily defined. Owing 

 to the great variability of pattern in Lefebvrei (by degrees of maturity 



