1898.] of the Coleoptcra of South Africa. 387 



GABATA, nov. gen. 



This new genus, which belongs to the tribe of the Euplectini, 

 is very closely allied to Euplectus. A reference to the descrip- 

 tion of Euplectus (Catal., p. 53) will be sufficient to show the 

 differential characters. The head is smaller, and much attenuate 

 in front, which gives it a somewhat triangular facies ; the three- 

 jointed antennal club is hardly conspicuous ; the last joint of the 

 maxillary palpi is much more elongate and fusiform ; the median 

 discoidal groove on the prothorax is wanting ; the seventh ventral 

 segment of the abdomen is very different, being small, transverse, 

 and without carina. 



With the exception of the different shape of the last joint of the 

 maxillary palpi, which is not a very important character, the much 

 more important difference in the structure of the seventh ventral 

 segment of the male, the differences between this new genus and 

 Eiqjlectus consists merely in plastic modifications which might 

 otherwise be considered as purely specific. 



In a paper upon the tribe of Eiqilectini, which is being now 

 printed, I have shown that such plastic modifications have a great 

 value, and become generic characters, on account of their constant 

 coincidence with important sexual modifications which are to be 

 found in the seventh ventral segment of the male. 



In Euplectus and some other genera this seventh segment is large, 

 rhomboidal, and has a longitudinal carina which is nothing else but 

 the indication of a cleavage of this segment, which opens longitudi- 

 nally on both sides at the middle, to allow the extrusion of the 

 penis ; in some other genera, instead of a longitudinal cleavage, it 

 is an operculum, which is lifted to allow the penis to protrude ; in 

 other genera this seventh ventral segment is small, more or less 

 transverse, and hinged in such a way as to leave, when opened, 

 between itself and the last dorsal segment, an opening for the 

 extrusion of the penis ; such is the form of the seventh ventral 

 segment in this new genus. 



I consider such sexual modifications as very important and of 

 generic value, but unfortunately they are to be found in the male 

 only, and it would be impossible for the females to be identified 

 without the adjunction, as generic characters, of those plastic modi- 

 fications which, by themselves, would not be sufficient to warrant 

 the creation of a new genus. 



