1897.] of tlie Coleoptcra of South Africa. 67 



to ascertain which is the female ; the head, however, is distinctly 

 smaller in that sex, the sides are oblique, not rounded, the sulci are 

 much larger and more distinctly marked and also not arcuate ; the 

 antennae are not so broad, and the prothorax neither so broad nor so 

 rounded. 



This species exhibits a very peculiar and extremely rare case of 

 polymorphism in the male sex, of which we know three forms, two 

 of which are veiy distinct from that of the female owing to the 

 large and deep excavation on the under side of the head, but the 

 third form is almost entirely similar to the female, except that the 

 shape of the ventral segments of the abdomen assume the concave 

 form peculiar to the male, and that the last segment is impressed. 

 Such males are hardly distinguishable from the females, unless the 

 penis protrudes. 



V ery abundant in the neighbourhood , of Cape Town (Newlands), 

 together with R. incerta. Typical males are not so numerous as the 

 females, and of the two varieties of that sex /3 and y appear to be 

 very scarce. 



Eaffrayia nasuta, 

 Plate XVI., fig. 10. 



Oblong, somewhat convex, ferruginous, rufous or testaceous, 

 covered with a pale pubescence ; legs and last joint of antennae 

 lighter in colour ; head rather large, slightly rounded on the sides, 

 attenuate in front, sulci strong, oblique, vertex with a long carina ; 

 eyes minute ; antennae short, thick, first joint shorter than usual, 

 second quadrate, rounded, third slightly transverse, eleventh briefly 

 ovate, subconical, and abruptly acuminate ; prothorax cordate, a 

 little broader than the head, convex, slightly sinuate laterally behind, 

 lateral foveas elongate, median sulcus variable in length, sometimes 

 obsolete, the transversa one strong, angular in the middle ; elytra 

 longer than broad, rugosely striate transversely but in a desultory 

 manner, attenuate at base, shoulders absent, dorsal sulcus strong, 

 disappearing in the median part ; first dorsal ventral segment large, 

 hardly impressed transversely at base ; metasternum convex and 

 simple. Length 1-40 mm. 



Female : Head truncate in the anterior part, sulci connected in 

 front. 



Male : Frontal part of head slightly produced between the 

 antennal tubercles, anterior sulci not connected ; under side of head 

 with a large fovea, much transverse, geminate, and the posterior 

 margin of which is sinuate ; last abdominal ventral segment 

 obsoletely impressed. 



