166 W. A. SANDS 



post. However, there is no doubt as to the true identity of M. sorex and its genuine 

 distinctness from M. giffardii. 



Material. Guinea : Mamou, io° 20' N., 12 15' W., 1912-13 (F. Silvestri), 

 syntype soldiers and workers, M. sorex Silvestri, Silvestri Coll., Lab. Zool. Sc. Agr., 

 Portici, and A.M.N. H. 



Ghana : 17m. N.E. of Gambaga on Bawku Road, 6. hi. 1959, and 12m. N. of 

 Techiman on Wenchi Road, 29. hi. 1959 (W. A. Sands). 



Nigeria : Western Region ; Ikeja, 10. h. 1955 (W. V. Harris) ; Benin Prov., 

 Sobo Plain, Obanokoro, 7. hi. 1957 (W. Wilkinson) ; between Shagamu and Ijebu- 

 Ode, 14. xh. 1957 (W. A. Sands). Eastern Region ; Port Harcourt, 18. iv. and 

 8.xi.i957, and Onitsha, 6.xi.i957 (W. Wilkinson). 



Material in British Museum (Natural History) unless otherwise stated. 



M. sorex, like its congeners, has been recorded from the mounds of other genera. 

 It is more widely distributed than M. giffardii, having apparently become more 

 tolerant of the marginal conditions of riverain and relict forest patches in the 

 savannah zones, and has crossed the Dahomey-Togoland gap to the Nigerian rain 

 forest. It has not however been recorded from the Congo forest block proper. 



TARDITERMES Emerson 



Tarditevmes Emerson, i960 : 15. Type-species by original designation, Tarditevmes contra- 

 color Emerson, i960. 



Imago. Left mandible with apical tooth very long, distance from apical to first marginal 

 over 3 times that from first to third marginals (left mandible index 3-17), cutting edge between 

 the latter entire, slightly concave, gap between third marginal and molar prominence about 

 half as wide as this cutting edge, small subsidiary tooth visible in gap in surface view ; right 

 mandible, apical and first marginal as left, second marginal absent, molar plate with no marked 

 irregularity of outline in surface view, and no ridges. Postclypeus, width 2-1 times length, 

 moderately inflated, anterior margin convex, sinuate. Fontanelle a light round spot surrounded 

 by an indefinite pale patch with lateral arms. Eyes very slightly set out from sides of head. 

 Pilosity of head short and even with scattered longer setae. Pronotum almost semi-circular 

 with rounded corners. 



Soldier. Monomorphic. Nose long, thick, conical, tapering to large fontanelle. Vestigial 

 mandibles without points, labrum with sinuate anterior margin. Head capsule not constricted, 

 rounded rectangular in plan and wider than long to base of nose. Antennae 13 segmented. 

 Head setae confined to nose tip apart from scattered microscopic hair-like setae on head and 

 nose. Abdominal tergites with minute setae, longer towards posterior ; sternites with short 

 setae and longer on posterior margins. 



Worker. Mandibles as imago, except right molar plate weakly indented near base and with 

 more pronounced anterior and posterior flanges (left mandible index 3-23). 



According to Emerson (i960), the imago of Tarditermes is larger than all its nasute 

 relatives except the neotropical Angularitermes. This is true but the recently 

 discovered imago of Mimeutermes edentatus Sands to a large extent bridges the gap. 

 Other features of the latter species appear to indicate a relationship with Tardi- 

 termes, including the characteristic slow movement of the neuter castes in life. The 

 imago of Tarditermes most closely resembles Mimeutermes in the widely curved 



