SCIENTIFIC NOTES. 303 



antennae are comparatively short and stout, ihe third joint but Httle longer 

 than the second, and very little shorter than the fourth ; the anterior 

 angles of the thorax are rounded and deflexed, and the callus is con- 

 founded anteriorly with the margin." These features are fully delineated 

 in the plate issued with the 1861 Annual. Cox {Handbook of Coieoptera, 

 1874) tabulates by the joints of antennee and shape of elytra, and also 

 states that ''the antennee and legs [of Z). coinari {discolor)] are shorter 

 and thicker," and elytra more coarsely j^unctured. Canon Fowler 

 {Coleop. Brit. Isles) says: — It {discolor) may "be easily known by 

 having the antennas comparatively short and stout, with the third joint 

 less elongate, and only a little longer than the second, and especially by 

 the fact that the anterior angles of the thorax are rounded and deflexed, 

 and the lateral callosities are much less marked and are confounded 

 anteriorly with the margin ; the antenucC and legs are sometimes partly 

 ferruginous." The same authority also gives the preference to sericea 

 in size. It would thus appear that an extreme form, having short and 

 stout legs and antenna, with very slightly marked tubercle, and elytra 

 parallel-sided, would constitute what is usually known as D. discolor 

 {coinari). All other forms, of which there are many, including those 

 with long, medium, and short antennee ; with tubercle slightly " hooked," 

 and also blunted or nearly absorbed ; legs long or short ; elytra parallel- 

 sided, or narrowing towards apex ; these would all come under D. sericea. 



It was pointed out by Mr. J. W, Tutt, at the meeting of the City of 

 London Entomological Society, December i8, 1890, that the black 

 forms of D. sericea exhibited, appeared to him to be of an uniform 

 small size. This observation might perhaps tend to explain the darker 

 colouring, but very little else. 



The types exhibited by Mr. Newbery showed the Scotch form of 

 discolor, as discovered by Mr. J. Foxcroft, in Perthshire, in 1854 ; also 

 South of England forms of discolor and sericea, and the intermediate 

 forms. The question which now presents itself is, " What constitutes 

 a species in this case?" One or two of the distinguishing points of 

 discolor may be found in sericea specimens ; but if the three are com- 

 bined in any one insect, then, according to our authorities, it is called 

 discolor. The matter may be thus summed up : the insects described 

 as sericea and discolor are probably varieties of one and the same 

 species, or else we are unacquainted with the true D. discolor. It may 

 be as well to add that these forms occur together at the Black Pond, 

 Esher, Woking, Shepperton, Sunbury, Wimbledon, Deal, Walthamstow, 

 and many other localities, generally in June and July, on rushes, Spar- 

 ganium, reeds, etc. 



D. braccata, Scop. — Known formerly as D. nigra, F. A large, 

 robust species, without impressions on elytra. Taken in profusion 

 about 1886, by Mr. Bedford Pim and the Rev. Theodore Wood, at 

 Pegwell Bay, Also taken by Mr. Heasler, at Deal, in 1890 ; and by 

 Mr. Cripps, at the Norfolk Broads. The insect is nearly always of a dark 

 violet or black colour, and occurs on Phragniites, etc., in June and July. 



D. affinis, Kunze. — The last of the genus. A much smaller insect 

 than the preceding, and on this account readily distinguished trom D. 

 braccata. It occurs at Walthamstow, among Sparganiuin, on the large 

 ponds in that locality. Also taken at Wimbledon by Mr. Newbery ; by 

 Mr. A. Piffard, Herts. — G. A. Lewcock, 73, Oxford Road, Islington, N. 



