BELOSTOMA. 37 



Diplouvclius subrliombeus, Mayr, Verh, z -b. Ges, Wien, xxi, 

 p. 437 (1871j. 



A little broader than /S. rusticum, head shorter and broader, 

 posterior angles of pronotum a little more obtuse and less acute, 

 antei'ior tarsal claws longer. In the Montandon collection of 

 Belostomatidae acquired by the British Museum there is a cot_ype 

 of Dufour's species S. molestum, and another determined by Mayr 

 as his S. siihrhomheus, which I cannot separate, and which are 

 evidently conspecific, differing only in size, the last being 

 smallest. 



Length 13| to ITj millim. 



Hab. Kashmir ( Vienna Mus.) : Calcutta Tanks {Ind. Mus.). — 

 Malacca {Coll. Sir/n.). 



Genus BELOSTOMA. 



Belostoma, Latr. Gen. Crust, et Ins. iii, p. 144 (1807) ; Amy. 8,' Serv. 



Hem. p. 427 (1843); Fieb. G-n. Hydroc. p. 21, t. 2 D (1851); 



Duf. Ann. Soc. Ent. Ft: 1863, p. 379 ; Stdl, Hem. Afr. iii, 



p. 182(1865); Mayr, Verh. z.-b. Ges. JF^eji, xxi, pp. 402 & 422 



(1871). 

 Belostomum, Burm. Handb. Ent. ii, 1, p. 195 (1835), 

 Amorgius, Stal, Hem. Afr. iii, p. 179 (1865). 



Type, B. indicum, Lep. & Serv. 



Distribution. Eastern Palaearctic and the other great zoo- 

 geographical regions. 



Body very large, narrowly ellijjtical ; head before eyes a little 

 conically produced, and between the eyes narrow ; rostrum very 

 thick, second joint much the longest ; pronotum trapezoidal, 

 anteriorly centrally truncate and posteriorly moderately sinuate ; 

 scutellum a little broader than long ; hemelytra with distinct 

 membrane provided with longitudinal veins ; legs of moderate 

 length ; anterior coxae short, not extending beyond the base of the 

 presternum ; femora compressed, anterior femora incrassate and 

 sulcated beneath ; posterior tibiae and tarsi ampliately compressed ; 

 tarsi two-jointed ; anterior tarsi with one claw, intermediate and 

 posterior tarsi provided with t\AO. 



These large and widely-distributed insects, though aquatic in 

 habit, are more frequently met with on their land excursions. 

 They are greatly attracted by light, and are frequent visitors to 

 the electi'ic lights now so common on the roads in most civilised 

 communities. At Trinidad, where the largest species is found, 

 it is known by the name of the " Electric Bug," and in the 

 Transvaal I took most of the South-African species {B. niloticum) 

 at the lights of Pretoria. Its jH'oboscis is capable of producing 

 a very painful puncture, of which I have had more than one 

 experience. 



Only one very widely-distributed species is found in the fauna 

 of British India. 



