PKOGRESSIVE MELANISM IN LEPIDOPTERA. 167 



(Prideaux, Fenn, Eaynor, etc.), only light and medium recorded, except 

 occasional suffused specimens from Derby (Hill), Walsall (See), and 

 Farnborough (Hewitt) . 



Hemerophila abruptaria. — In the north of England the species is 

 not common. Eecords from Durham (Robson), Yorkshire (Hewett), 

 Lincoln (Raynor), Norfolk (Atmore, Pitman), Notts (Addison), Cambs 

 (Farren), Sussex (Christy), Surrey, Bristol (Prideaux), and Stafford 

 (Woodforde), mention only the light form. The dark variety is 

 characteristic of London and its suburbs ; it has also been recorded 

 from the New Forest (Sequeira), but is probably very rare there. In 

 London it is much less common than the type (Harris, Fenn, Quail). 

 When crossed with the type intermediates are not produced, but the 

 results suggest that the dark form is a Mendelian dominant. Mr. 

 Harris got the following results. First cross gave 11 light, 9 dark. 

 Two of these darks paired together, gave 39 dark, 18 light. Of 

 these — 



(1) Dark J xdark <y gave 67 all dark. 



(2) Light ? X light t? gave 18 all light. 



(3) Light ? X dark ^ gave 23 dark, 6 light. 



(4) Dark J x light c? gave 33 dark, 15 light. 



Also Mr. T. H. Hamling {Trans. City of London Ent. Soc, 1905, 

 p. 5):- 



(1) Dark 5 X light J* gave 9 light, 11 dark. 



(2) Light 5 X dark ^ gave 8 light, 8 dark. 



(3) Dark 5 xdark <? gave 17 light, 48 dark. 



(4) Light ? X light g- gave 18 light, 1 dark. 



Boarmia repandata. — Very variable. In the south of England 

 and midlands a light brown form seems prevalent ; in the south, 

 South Wales, and more rarely in the north, the banded var. conversaria 

 occurs. In the north of Ireland, Scotland, and especially in the 

 Scottish Islands, a grey variety is prevalent. In the north of England 

 specimens are found darker than in the south, and a black form now 

 occurs, and seems to be spreading ; it appeared first in south York- 

 shire. Huddersfield, black first recorded in 1888 ; in 1900, 20-25% 

 black with or without white line, remainder brown. Probably became 

 gradually darker (Porritt). Rotherham, Sheffield, black or very dark 

 now prevalent, has increased in the last fifteen years (Brady, 

 Doncaster, Hall). York, very dark and black absent (1900, Hewett). 

 Durham and iSTorthumberland, brown and dark with distinct 

 markings, prevalent ; very dark and black rare ; conversaria formerly 

 common, now rare (Robson, Brady, Rosie). Chester, Delamere (Arkle, 

 Collins), Market Drayton, medium prevalent, but dark and black (less 

 black than darkest Yorkshire specimens), not uncommon. At Market 

 Drayton darker forms are prevalent in fir- woods nearer Potteries ; type 

 form prevalent in oak-woods, further west (Woodforde) . Black speci- 

 mens are recorded from the Furness district (Morgan), Saltburn, 

 Galway (Dillon), dark, but not black, from Gloucestershire (Davis), 

 Wigtownshire (Gordon), Linlithgow (Hewett), Kent, London (Hewett, 

 Mera). Returns from midlands. East Anglia, and most of the 

 southern counties mention only light to medium ; var. conversaria 

 from Durham (Robson) ; Swansea (Robertson), Bristol (Prideaux), 

 Cornwall, New Forest (Ogden). 



Boarmia rhomboidaria. — In the south, except London, the prevalent 



