44 YORKSHIRE NATURALISTS' UNION. 



Colymbetes grapii Gyll. This species has not been found 

 in any Yorkshire locality but Askham Bog. There it is 

 sometimes quite plentiful, especially in a very shallow moss- 

 grown pond, or rather morass. /Appears early in March. 



4. Central.- — Askham Bog (IV. Ifeyisee Zoo/., 1857, 

 XV. 5410, and £. M. M., May 1868). Also taken by H. 

 Hutchinson and W.C.H. 



Colymbetes pulverosus Steph. 



4. Central. — Askham Bryan, 1830 {A. Wright, 

 November 25th, 1830, in Loudon's Mag., 1831, iv. 165). 

 N.B. — This record has never beein confirmed. 



Colymbetes bistriatus Berg. Local. 



2. N.E. — Marton, 1839 (Steph., Man., 1839, p. 72). 

 4. Central.— Strensall, July 1883 (W.C.H.). The 

 record from Askham Bog (E. M. M., June 1872, ix. 12) 

 : can hardly be correct. 



Colymbetes exoletus Forst. Locally abundant. 

 2. N.E. — Scarborough (R. Lawson). 



4. Central. — Askham Bryan, 1830 (y^. Wright, Loudon's 

 Mag. N. H, 1831, iv. 165). Also taken by Archdeacon 

 Hey (Zool., 1857) and H. Hutchinson (E. M. M., 1872). 

 It is still abundant in one pond ( W.C.H). 



5. S.W.— Wakefield (E. B. Wrigglesiuorth). 



Ilybius fenestratus F. Scarce and local. 

 2. N.E.— Gormire (?^C.^). 

 4. Central. — Stamford Bridge (Rev. W. W. Fowler). 



Ilybius fuliginosus F. A very abundant species, affecting 

 small ditches and ponds. 



1. S.E.— Driffield (fKC^). 



2. N.E. — Co ciih'^xn (W.C.H); ^C2ixhorou^(R. Law son). 



3. N.W.— Richmond (?KC.Z^); Masham {^. 7'^//^r^, 

 Nat., 1879, V. 22). 



4. Central. — York district, generally, in abundance 

 (W.C.H). _ . . 



Trans. Y.N.U., 18S5 (pub. 1S88). Series D. Vol. 3. 



