Genus PIERIS, Schrank , 1801 
THE GREEN-VEINED WHITE 
Pier is ncipi (Linn., 1758). 
(Plate XXVII, facing page 304) 
Haunts and Distribution. Except in the extreme north, 
the Green-veined White is common and generally distributed 
throughout the British Isles, but it is much more restricted 
in its haunts than either the Large White or the Small White. 
Abroad it ranges over Europe, North-west Asia, Siberia and 
Japan. It frequents the less-cultivated parts of the country 
and prefers damp meadows, marshes, the outskirts and ridings 
of woods, also fields of different kinds of the Cruciferae, 
especially those in bloom. 
Unlike the other two common whites, P. napi is not 
destructive to garden produce. 
Migration. In The Entomologist , Vol. LXVI, p. 209 and 
p. 231, are the following records of the migratory movement of 
P. napi . Dr. F. C. Garrett, Northumberland, records : " A 
flight of white butterflies began to pass Catleugh about midday, 
May 2i$t, 1933 ; they were flying in a westerly direction. 
Large Whites were considerably in the majority, Green-veined 
were fairly well represented, but only odd Small Whites 
passed. The flight continued all next day/' Mr. G. Bolam 
also records: “ P. napi on May 21st at Alston, Cumberland, 
from midday onwards, flying N. or N.W. in exceptionally fine 
weather. Very abundant for some days, drifting over the 
moors up to 2,000 feet, sometimes in hundreds, in small com¬ 
panies usually, but great in aggregate. Numerous up to the 
end of July.” 
Time of Appearance. This is one of the earliest butterflies 
to emerge from the pupa in the spring. It sometimes 
makes its appearance at the end of March, but its normal 
time on the wing is from the end of April, throughout 
May and early June. Eggs laid by these vernal butterflies 
produce pupae in June and July; part of these emerge 
in July and August, resulting in a second brood of 
butterflies, while the other portion remain in the pupal state 
throughout the winter and produce the early spring emergence. 
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