84 REVISION OF THE AMYCTERIDES, ii., 



In regard to the long anal forceps of the male, which must 

 remain the main distinctive character of Psalidura, dissection of 

 a typical Talaurinus discloses the fact that these organs are pre- 

 sent, but more or less membranous and rudimentary, the com- 

 ponent parts being more or less continuous. In certain species, 

 however, the blades of the forceps are more strongly developed, 

 are chitinous, and their apices protrude at each side of the anal 

 excavation. Also in a few species, e.g., T. M-elevatus Lea, the 

 ends of the forceps, though joined together by membrane, are 

 separated by the intervention of a chitinous vertical plate, as in 

 Psalidura. If we try to separate off such species, we find that 

 they merge, by almost imperceptible degrees, into others possess- 

 ing normal structure The same remark applies with equal force 

 to the rostral characters. Macleay regarded the rostrum in such 

 species as T. typicus and T. alternans as typical of the genus. 

 Its chief characters ai'e given above, but I should add that the 

 external ridges are continued back along the forehead, and the 

 forehead itself is concave at the base of the rostrum. Compara- 

 tively few species, however, have the rostrum so formed, though 

 the main features are always traceable, with the exception of the 

 internal rostral ridges; these may be entirely obsolete, as in T. 

 verrucosus, where, however, the median area is depressed, and in 

 no way raised or carinate as in Sclerorrhinus. In other species, 

 the rostrum is shorter, and approaches more nearly to that char- 

 acteristic of Psalidura. Other more aberrant forms of rostra 

 have led to the separation, from the genus, of the genera A^oto- 

 nophes, Sclerorrhinella, Lataui-inus, etc. 



The prothorax is variable in shape and granulation, and lacks 

 the ampliate form, anteriorly produced over the head, that is 

 found in most species of Psalidura. 



The elytra present the widest degree of difference in sculpture, 

 and INIacleay has utilised this feature for dividing the group into 

 sections : Granulati, Tuberculati, Costati, Foveati and Echinati. 

 While, for convenience, 1 have retained most of these divisions, I 

 believe they cannot be rigidly adhered to, some species showing 

 structure that might reefer them to two or more groups. Macleay 

 regarded the sections Tuberculati and Costati as typical, Granu- 



