59 
southern $ and $ , state that it is found especially in the north of 
England, but Stainton, 1859, records it from all over England. With 
regard to Ireland the position is somewhat different. The insect is 
mentioned without locality in Joseph Greene and Hogan’s list, 1857, 
but Birchall, in 1867, had not met with it in Ireland, though he admits 
that three-quarters of the country was still terra incognita at that date. 
Kane, in his list, “ Entomologist,” 1897, p. 215, says that it is very 
local, but abundant where it occurs, and ab. flavescens has been taken 
in Meath. 
The white type form is the common one, all three in the Dublin 
Museum are of this colour, and entomologists from Enniskillen, Kerry, 
and other countries took only types: (Sir Charles Langham, Com¬ 
mander Gwatkin-Williams, and Mr. Dudley Westropp). From this 
evidence I draw the following conclusion that the type, the small 
white northern race, entered Scotland by the old land bridge between 
that country Scandinavia, spread down and occupied north England, 
crossed to Ireland by this land bridge, which united Scotland and 
Ireland and spread over the whole country. In Ireland much des¬ 
truction of fir woods took place, but probably some remained, and the 
insect persisted. Replantation has taken place, and though the insect 
has spread, and, according to the recent evidence of the Rev. John 
Bristowe, is still spreading, it is still local. 
In England, if it ever inhabited the southern counties, it died out 
with the destruction of all fir woods. 
Reafforestation took place, but the insect only established itself in 
recent times, and was still very rare indeed in 1800. The form found 
was the large ab. Jlaveseens, and it probably came from France—there 
is proof that the female travels great distances at night—where this 
form is predominant, spread rapidly and intermingled with the small 
northern race which spread down to meet it. 
NOTES ON THERA VARIATA (SCHIFF.) AND T. OBELISCATA (HB.) 
(Read May 6th, 1913, by L. B. PEOUT, F.E.S.) 
Probably—notwithstanding the long time which it takes for a new 
idea concerning an assumedly well-known species to obtain a fair hold 
upon the average imagination—most ordinarily -well informed 
Lepidopterists are, by this time, at least aware that there is a “ Thera 
variata question ; ” that is to say, that some misguided person has been 
doing something of late to disturb the calm contentment with which 
the majority have been ignoring the common pest of our pine-woods, 
or the minority (more zealous over Geometrid variation), keeping an 
eye open for chance “ abs.,” and perhaps congratulating themselves 
that variata was by no means such a misnomer as a good many other 
names which might be mentioned. But, as I have no means of 
knowing how far my audience has digested my article in “ The 
Entomologist ” (xlv., 241), or understands exactly what has happened 
regarding this (or these) species, I think it will be well to re-state the 
xxii.-xxiii. 
