166 APPENDIX. HYDBOMETBIDJE. 



tibise ; the anterior tarsi short, robust, about half as long as the 

 tibiae ; intermediate legs much longer than posterior legs, inter- 

 mediate femora nearly as long as body, the intermediate tibise a 

 little shorter than the femora, intermediate tarsi about half the 

 length of the tibia?. 



The above description is taken from a number of apterous forms 

 received from different localities. Nacebus is allied to Rhayado- 

 tarsiis, Bredd., from which it differs by the structure of the head 

 and thorax. 



2936. Nacebus dux, Dist. A. M. N. H. (8) v,p. 153 (1910). 



Body above and beneath, antennae, rostrum, and legs black ; 

 pronotum, anterior femora (excluding apices), acetabula, coxae 

 and trochanters ochraceous ; disk of mesonotum and abdomen 

 distinctly more opaque in coloration ; structural characters as in 

 generic diagnosis. 



Length (inch anal append.) 4 millim. 



Hob. Calcutta. Lower Burma ; Mudon, Amherst Distr. 

 (Annanda le). 



At Calcutta this species was found in the tanks. 



