ACRIDIDjE. 633 



** Keel of the prothorax very slight. 



t Hind tibiae not blackish. ... Ceramicum. 



tf Hind libiae blackish. - - tenebriferum. 



b. Hind border of the prothorax angular. - contractual. 



A. transiens and A. tenebrosum are the most typical of the preceding 

 species. A. contractum is slightly aberrant. 



ACBIDIUM TENEBRIFERUM. 



Fcem. Piceum, subtus fulvum; caput el prothorax luteo interruple 

 bivittuta ; caput breve, fas tigio subhexagonali, fronte scabra luteo 

 varia ; prothorax scaber, vix carinatus, margine postico valde rotun- 

 da to ; prosterni spina conica, breviuscula, subacuta; pedes fulvi, 

 tibiis tarsisque quatuor anterioribus piceis, femoribus posticis nigro 

 binotatis, tibiis tarsisqiie posticis nigricantibus ; ala anticce corpore 

 multo breviores. 



Female. Piceous, moderately stout, tawny benealh. Head and pro- 

 thorax with an interrupted luteous stripe on each side. Head short ; tip 

 of the vertex flat, subhexagonal ; front scabrous, partly luteous ; keels 

 strongly marked ; inner keels nearly parallel; outer keels diverging slightly 

 towards the face. Eyes much rounded on the hind side. Prothorax 

 scabrous, with a very slight keel ; transverse impressed lines strongly 

 marked ; fore border nearly straight ; sides slightly rounded ; hind border 

 much rounded. Prosternal spine conical, slightly acute, rather short. 

 Legs tawny ; four anterior tibiae and tarsi piceous ; hind femora with two 

 black marks on the outer side; hind tibiae and hind tarsi blackish, the 

 former a little shorter than the hind femora. Fore wiugs much shorter 

 than the body. Hind wings cinereous, pellucid; veins black. Length of 

 the body 13 lines; expansion of the fore wings 21*lines. 



a. Celebes. From Madame Ida Pfeiffer's collection. 



Australia. 



A. Size very large. .... maculosum, 



B. Size moderate or small. 



a. Tip of the vertex depressed. 

 * Antennae not flattened. 



f Prothorax luberculate. - tuberculatum. 



ft Prothorax not tuberculate. 



J Prosternal spine slightly forked. - furciferum, 



$ Prosternal spine not forked. 



J Prosternal spine long, conical at the tip. - - angustifrons. 



Prosternal spine very obtuse. - - pynhocnemis. 



Prosternal spine hardly long, semicircular at the tip. obtusum. 



Prosternal spine acute. ... virescens. 



** Antennas flattened. 



f Tip of the vertex hexagonal. - exclusum. 



ft Tip of the vertex subheptagonal. - alienum. 



b. Tip of the vertex not depressed. - pilipes. 



A. angustifrons, A. obtusum, and especially A. pilipes and A. exclusum, 

 are aberrant species of the genus. 



