A.^ 



116 Mr. F. Balfour- Browne on the 



niediaii tarsus of the S is strongly excised in the posterior 

 margin, but in hroioneanus the segment is rather narrower, 

 thouo-h this is variable and not a reliable distinction. 

 Dr. Sharp tells me that " in hroioneanus the tip of the first 

 joint [of the median tarsus of the c? ] comes off at a more 

 abrupt angle^ the second and third joints are less dilated, and 

 the fourth is shorter " ; but, after drawing a number of 

 examples with camera lucida, I am quite unable to appreciate 

 these dif^ierences. 



General Summary of Characters. — 



f 1. Geueral form variable, usually with elytra Avidest a little beliind 

 the shoulders. 



2. Thorax not more than twice as hroad as lonp^, the sides more or 

 less straight, more convergent anteriorly in nomax, less in 

 broicneanus. 



3. Thoracic strife usually long and straight. 



4. Elytra with blaclf lines sometimes spreading and irregular and 

 sometimes nearly regular. The most usual marking is not 

 unlike that of H, Jiuviatilis, the form of which species distin- 

 guishes it from this. 



il. Ant. tarsal claws practically equal. 

 2. Basal segment of median tarsus with posterior side strongly 

 excised. 

 P, ( 1. Elytra apparently always in Britannic specimens completely 

 + • 'j covered with fine puncturation. 



As to ffideagal characters, note the smallness of the " hood," 

 •which is almost absent, and the well-developed saccular 

 region and its ^' wing." 



4. H. icehichei, Gerh. 



This species was first recognized as British by Newbery (14), 

 who, however, identified it as H. immaculatus, Gerh., an 

 error which was corrected by Edwards. In our islands this 

 species has an extensive range, from the Hebrides in the 

 north to the extreme south of England ; and, although there 

 are at present many gaps in its recorded distribution, these 

 will no doubt be filled up inthe course of time. Like Il.fluvi- 

 atilis, ivehncJcei occurs freely in running water, but, unlike it, 

 it is, especially in the north and west, a lake-species, and is 

 usually, according to my experience, the most abundant 

 species of the group in those districts. 



I have taken it in the north-east and south-east of Ireland 

 (Derry, Antrim, Down, Armagh and Wicklow, Wexford, 

 Waterford, and Kilkenny) and in Westmeath, and have 

 seen specimens from Mayo W. In Scotland I have taken it 

 in the Outer Hebrides (Lewis), Inverness E., Lanark, Ken- 

 frew, Ayr, and Kirkcudbright, and have seen specimens 



