SCIENTIFIC NOTES. 301 



Farnham, Wanstead, Walthamstow, etc., chiefly on Sparga)iiiim. Mr. 

 Heasler took a number at Deal in 1S90. Messrs. Newbery and Cripps 

 have also captured it in Kent ; Mr. Bennett at Hastings ; and Mr. R. 

 Gillo (on Iris) in the Bath district. 



D. bicolora, Zsch — Formerly called D. sagittaria;, F., in Sharp's 

 Catalogue {i^T i) and Fowler and Matthew's Catalogue (1883). The 

 species is readily distinguished from the preceding in being unicolorous, 

 broader, and having more impressions. Generally of a lighter colour, 

 but occasionally one meets with dark, coppery specimens, and some- 

 times these dark varieties are mistaken for Z>. limbata by the inexpe- 

 rienced coleopterist. I have never taken very many, at the most only 

 eight or nine in one day. My series was captured at Farnham (Surrey), 

 and on the flashes of Basingstoke Canal ; principally on the yellow iris 

 and the arrowhead. Also taken at Deal by Mr. Heasler in 1890. 



D. obscura, Gyll. — First recorded in the Entomologisfs Annual {i'66o) 

 as being taken by Mr. Constantine near Glasgow. " Very nearly allied 

 to D. lemnce (our present D. limbata), from which it differs in its more 

 sombre colouring, in having the prothorax transverse, the anterior 

 angles more pronounced and slightly reflexed, and without tubercles, 

 and the base of the elytra, from the humerus to within a short distance 

 of the suture, thickly strewn with punctures " (y^«;?z^fl/, i860, p. 147)- 

 Canon Fowler {Coleop. Brit. Isles) states that it is taken "on flowering 

 Scirpus and Carex in May." The localities given are : Arundel (S. 

 Stevens) ; Mabberley, Cheshire (Chappell) ; Scotland, Solway district, 

 Dumfries (Sharp and Lemmon) ; also recorded doubtfully from the Tay 

 district. I know of nothing authentic respecting its occurrence in the 

 south of England. 



D. thalassina, Germ. — Frequently confounded with D. linearis, from 

 which it may be readily distinguished by the teeth on the hinder femora. 

 The legs also are unicolorous. This is perhaps the commonest species 

 of the genus in Surrey. I have swept as many as 250 specimens in one 

 day. It is found at the Black Pond, Esher, on the banks of Basingstoke 

 Canal, Farnham ; also at Sunbury, Wanstead Park, Deal, Hastings, and 

 many other localities. This species also has a melanic tendency, espe- 

 cially is it the case with those found at Woking, and sometimes the elytra 

 are entirely purple. 



D. inipressa, Payk. — Said to be closely allied to the preceding species. 

 Beyond having seen some specimens m Mr. Champion's collection, I 

 know nothing of it. 



Z). simplex, F. — Familiar to most coleopterists as D. linearis, Hoppe. 

 This species is generally supposed to be the commonest of the genus. 

 It is certainly common at Hackney Marshes, also in the small streams 

 at Sunbury and Shepperton, and seems to have a preference in these 

 localities for running water. I have not found it at Woking, and know 

 of but a single specimen captured near the Black Pond, Esher. There 

 is no possibility of mistaking this for any other species. It is found ox\ 

 Sparganium, rushes, and other aquatic plants in June and July. 



D. vulgaris, Zsch. — Named as D. typhce, Ahr., in Sharp's Catalogue 

 (187 1), and Fowler and Matthews' Catalogue (1883). Allied to the 

 preceding s]:)ecies, but could hardly be confounded with it, having a 

 broad reddishqmrple band running down each side uf the suture. The 

 band is sometimes of a deep blue, and occasionally it is so faint as to 



