660 Mr. R.. Shelford on the Studies of the Blattidae. 



Rhodesia, Loangwa R. (aS'. A. Neave) (Oxford Mus.) 

 Congo, Katanga and Lualaba R. {S. A. Neave) (British 

 Mus.), Umangi {Wilwerth) (Brussels Mus., Oxford Mus.). 



Hemithyrsocera nigerrima, sp. n. 



5 . Closely allied to H. vinula, but the antennae not incrassated ; 

 tegmina nniform piceous except for a narrow marginal band which 

 is testaceous and extends throughout the entire length of the teg- 

 mina ; radial vein of wing simple ; tarsi testaceous. 



Total length 10"5 mm. ; length of body 9'2 mm. ; length of 

 tegmina 9 mm. ; pronotum 28 mm. x 35 mm. 



Hob. Kamerun, Jaunde-Stat (Berlin Mus., type). 



Hemithyrsocera ridleyi, sp. n. (PL LXXX, fig. 15.) 



^ . Flavo-testaceous. Antennae setaceous, testaceous ; eyes 

 widely separated on vertex of head. Pronotum widely trapezoidal, 

 margins hyaline. Tegmina and wings exceeding the apex of the 

 abdomen, Tegmina with 19 costals, radial vein bifurcate from the 

 middle, anterior ulnar bifurcate, 7 discoidal sectors. Wings hyaline, 

 mediastinal vein 4-ramose, 16 costals slightly incrassated, radial 

 bifurcate from the middle, medio-discal area about 2^ times broader 

 than medio-ulnar, ulnar vein simple, discal area crossed by numerous 

 transverse venules, triangular apical area moderate, distinct. Ab- 

 domen above banded with fuscous, no scent-gland visible, supra- 

 anal lamina shortly triangular, apex sub-truncate. Sub-genital 

 lamina extremely asymmetrical, on the extreme left a blunt curved 

 process, on the inner side of this another blunt process tufted with 

 stiff brown hairs, the rounded apex of the lamina fimbriate, the left 

 style small situated to the right of the apex, the right style a large 

 sinuose structure. In addition there appear under the supra-anal 

 lamina a pair of bifurcate and denticulate processes which apparently 

 are not connected with the gonapophyses. Cerci 12-jointed, of 

 moderate lengths, apex acuminate. Femora very strongly armed 

 (front femora missing). 



Total length 13 mm. ; length of body 12 mm. ; length of tegmina 

 12 mm. ; pronotum 3 mm. x 4 mm. 



Hab. Singapore, Botanic Gardens {H. N. Eidley), 

 (Oxford Mus., type). 



The complicated nature of the secondary sexual ap- 

 paratus of this species is highly remarkable. 



