1881. J 197 



half, in $ about three-fifths, as long as the femur, the 3rd joint in ^ 

 as long as the 2nd. Nymph agile, with seven pairs of single abdominal 

 tracheal branchiae, all nearly alike in form, viz. : obtusely ovate or 

 obovate, and traversed lengthwise by a pinnately branched trachea, 

 irregularly subdivided. The median seta is usually about three-eighths 

 as long, the lateral setae about three-fourths as long as the body ; but 

 sometimes (e. g., in B. amnicus) the median seta is far more abbre- 

 viated. Type, B. binoculatas, L. Distrib., Europe and Egypt, Indo- 

 Malay region, Australia ; North, Central, and, perhaps, South America. 

 Some species of Callihcetis and Ba'etis have the front border of the 

 anterior wings variegated in one or in both of the sexes. 



(To he continued). 



DESCRIPTION OF ANOTHER NEW SPECIES OF DAMASTER. 

 BY GEORGE LEWIS. 



I have now from the West Coast an insular species of Damaster 

 which is very interesting to me, as the head and thorax show considera- 

 ble divergence from the form usual in the genus. The insect comes 

 from the island of Sado, where it appears to be rare, four specimens 

 only being obtainable last month, and these came from the mountains 

 eight miles from the coast. I characterize it as : 



Damaster capito, sp. n. 



Nigro-violaceus, corpore vix lato, capite prothoraceque latioribus, 

 validis, oculis subprominulis ; elytris granulosis, hand mucronatis. 



Sab. in ins. Sado. Long, cor p. 18 — 19 lin. 



Head and thorax violet-black, elytra dull black ; more robust in figure than D. 

 pandurus, with shorter legs, more robust tarsi, head, mandibles and thorax much 

 larger. The thickness of the head gives the region of the eyes a greater space, and 

 renders them much less prominent, viewed from above they project but little beyond 

 the outline of the head. The thorax is somewhat quadrate, widest in the middle, 

 its greatest breadth equalling its greatest length, which is 2j lines, and the posterior 

 angles are more acute than in any other described species. The thorax of D. pan- 

 durus measures, in an average specimen, 33 lines in width and 4 in length ; what D. 

 capito loses in length it gains in breadth. Elytra granulose, the stria? as usual 

 scarcely visible. 



In speaking of the dilated tarsi in the <$ of the northern species, 

 as compared to T>. blaptoides, it must be observed that in T>. rugipennis, 

 D. viridipennis, and the present species, the tarsi are stouter in both 

 sexes, but the difference in the $ and $ of any one is very little, not 

 more than in the large southern species. 



