144 APPENDIX. HYDROMETRIDA'. 



tibiae and all the tarsi black, anterior tibiae brownish ochraceous, 

 their apices black ; antennae with the first joint longest, fourth 

 slightly longer than third ; head moderately convex, longer than 

 broad ; pronotnm with the margins of the anterior area slightly 

 convex, a little transversely ridged between the humeral angles, 

 which are slightly prominent and then globosely posteriorly 

 deflected, the posterior margin sublaminate, the posterior area 

 sparsely coarsely punctate; hemelytra about as long as the 

 posterior femora ; intermediate and posterior femora about 

 equally long ; rostrum black, slightly passing the anterior coxae. 



Length <5 macropt. 8 millim. 



Hob. Nepal ; Soondrijal and Chonebal, Katmandu. United 

 Provinces ; Lucknow (Annandale). 



Allied to G. sahlbergi, Dist. 



GEBRIS TRISTAN. (Vol. II, p. 179.) 



This species, originally described and known only from Ceylon, 

 is now found to have a wide distribution in India and Burma. It 

 is also possible at the same time to supplement the description so 

 far as the fourth joint of the antenna is concerned ; this like the 

 third joint is fuscous. 



Add : Hab. Bengal ; Port Canning, Rajshai, Dhappa. Orissa ; 

 Sur Lake, Puri District (Annandale). United Provinces ; Naini 

 Tal, Kumaon (Annandale) Burma ; Moulmeiu (Annandale). 



Dr. Annandale found this species in brackish pools at Port 

 Canning and in fresh water at Dhappa. 



2918. Gerris raja, Dist. A. M. N. H. (8) v, p. 142 (1910). 



Head ochraceous, eyes black ; antenna? with the first joint 

 ochraceous, its apex black, remaining joints black or piceous ; 

 pronotum with two anterior and two large discal spots ochraceous 

 (in some specimens these spots are united in pairs) ; hemelytra 

 black ; body beneath, rostrum, and anterior femora ochraceous ; 

 apex of rostrum and linear streaks to the anterior femora black ; 

 tibia?, tarsi, and intermediate and posterior femora piceous or 

 black ; antennae with the first joint a little longer than second 

 which is shortest, third longest, fourth shorter than third but 

 longer than first ; head a little convex, longer than broad ; 

 pronotum with the humeral angles not prominent ; hemelytra 

 about as long as the posterior femora ; intermediate and posterior 

 femora subequal in length ; rostrum passing the anterior coxae. 



Length 5 millim. 



Hab. Travancore Coast ; Vurkalay (Annandale). 



" In small pools near sea-shore" (Annandale). 



By the relative lengths of the joints of the antenna?, and the 

 markings of the head and pronotum, this small species is distinctly 

 recognizable. 



