Insects in Great Britain . 
25 1 
flies give results agreeing with previous ones, except that the 
avoidance of Class B' is very slight, instead of, as usual, very 
great. 
Taken as a whole, then, we may say that these results 
support the Mullerian theory of flowers very well. Further 
facts in. support of it may be obtained by taking note of the 
flowers visited by each particular insect. One or two cases 
may be given. Among the butterflies Pieris napi was the 
most frequent visitor, going to io flowers, all but one ( Pim - 
pinella) in Classes B, B', H. Polyommatus phloeas , the next 
commonest, went to 7 flowers in these classes, and 1 other 
{Angelica). These two, with Epinephele janira , Pieris rapae , 
and Vanessa tirticae , were the only butterflies common in the 
district. 
Taking next the long-tongued bees, of which there are 
12 species — Apis mellifica , Anthidium manic alum , and 10 
Bombi (incl. Psitkyrus) — the bulk of the visits were made 
by the humble-bees (6 2 out of 72). Bombus muscorum L. 
was the commonest bee, and visited, usually in abundance, 
19 flowers, all but one (. Hypericum ) in the higher classes 
(B,B',H). b. terrestris was nearly as common (16 flowers), 
whilst B. latreillellus var. distinguendus , B. cognatus , and 
Psitkyrus quadricolor were seen only on 1 flower each. The 
hive bee offers an interesting list. The district is famous for 
its honey, and in the small village of Auchencairn there are 
over 100 hives. The heather was then in full bloom ( Cailuna 
and two species of Erica ) and attracted very nearly all the 
bees, which were abundant on it, even up to the highest 
hill-tops in the district (Ben Gairn, 1,250 feet). The only other 
plant that received any particular attention from them was 
Senecio Jacobaea , the most conspicuous and abundant plant, 
next to the heather. On this they were usually to be seen, 
especially in dull or cold weather, when they seemed dis- 
inclined to go to the moors. 
The short-tongued bees — 6 species : 3 of Halictus , 1 each 
of Andrena , Prosopis } Sphecodes — paid nearly all their visits 
to Class B'. On the Senecio they abounded, but they are 
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