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trums, are generally yellow or white. The blue delphiniums and aconites are highly specialised, abnormal forms, and doubtless, therefore, of more recent origin. Among the Caryophyllacea the red and purplish species are amongst those with highly specialised flowers, such as Dianthus and Saponaria, while the simple open flowers, which more nearly represent the ancestral type, such as Stellaria, Cerastium, &c., are yellow and white.

Take, again, the Primulaceæ. The open-flowered, honeyless species, such as Lysimachia and Trientalis, are generally white or yellow; while red, purple, and blue occur principally in the highly specialised species with tubular flowers. The genus Anagallis here, however, certainly forms an exception.

Among the violets we find some yellow, some blue species, and Müller considers that the yellow is the original colour. Viola biflora, a small, comparatively little specialised fly-flower, is yellow; while the large, long-spurred V. calcarata, specially adapted to humblebees, is blue. In V. tricolor, again, the smaller varieties are whitish-yellow; the larger and more highly developed, blue. Myosotis versicolor we know is first yellow and then blue; and, according to Müller, one variety of V. tricolor alpestris is yellow when it first opens, and gradually becomes more and more blue. In this case the individual flower repeats the phases which in past times the ancestors have passed through.

The only other family I will mention is that of the

Gentians. Here, also, while the well-known deep blue species have long tubular flowers, specially adapted to bees and butterflies, the yellow Gentiana lutea has a simple open flower with exposed honey.

Müller and Hildebrand1 have also pointed out that the blue flowers, which, according to this view, are descended from white or yellow ancestors, passing in many cases through a red stage, frequently vary, as if the colours had not had time to fix themselves, and by atavism assume their original colour. Thus Aquilegia vulgaris, Ajuga Genevensis, Polygala vulgaris, P. comosa, Salvia pratensis, Myosotis alpestris, and many other blue flowers, are often reddish or white; Viola calcarata is normally blue, but occasionally yellow. On the other hand, flowers which are normally white or yellow, rarely, I might almost say never, vary to blue. Moreover, though it is true that there are comparatively few blue flowers, still, if we consider only those in which the honey is concealed, and which are, as we know, specially suited to and frequented by bees and butterflies, we find a larger proportion. Thus, of 150 flowers with concealed honey observed by Müller in the Swiss Alps,2 68 were white or yellow, 52 more or less red, and 30 blue or violet.

However this may be, it seems to me that the preceding experiments show conclusively that bees do prefer one colour to another, and that blue is distinctly their favourite.

1 Die Farben der Blüthen, p. 26.
Alpenblumen, p. 492.

311

CHAPTER XI.

WASPS.

I HAVE also made a few experiments with wasps.

So far as their behaviour, when they have discovered a store of food, is concerned, what has been said with reference to bees would apply in the main to wasps also. I will give some of the details in the Appendix, and here only refer very briefly to some of the experiments.

Experiment 1.--Watched a wasp, which I had accustomed to come to my room for honey, from 9.36 A.M.to 6.25 P.M. She made forty-five visits to the honey, but did not bring a single comrade.

Experiment 2.-The following day this wasp began working at least, came to my room for the first time at 6.55 A.M., and went on passing backwards and forwards most industriously till 6.17 P.M. She made thirty-eight journeys, and did not bring a single friend.

Experiment 3.-Another wasp was watched from 6.16 A.M. till 6 P.M. She made fifty-one journeys, and during the day five other wasps came to the honey. I do not think she brought them.

Experiment 4.-Another wasp was watched from 10 A.M. to 5.15 P.M.; she made twenty-eight journeys,

and brought no friend. This wasp returned the next morning at 6 A.m.

Experiment 5.-A wasp was watched from 11.56 A.M. to 5.36 P.M. She made twenty-three journeys, without bringing a friend.

Experiment 6.-Another wasp between 6.40 a.m. and 5.55 P.M. made sixty journeys, without bringing a friend.

Experiment 7.-Another wasp between 7.25 A.M. and 6.43 P.M. made no less than ninety-four visits to the honey, but did not bring a single friend.

Experiment 8.-I watched a wasp on September 19. She passed regularly backwards and forwards between the nest and the honey, but during the whole day only one other wasp came of herself to the honey; this wasp returned on the 20th, but not one other. The 21st was a hot day, and there were many wasps about the house; my honey was regularly visited by the two marked wasps, but during the whole day only five others came to it. September 22.-Again only one strange wasp came, up to one o'clock.

September 27.-Only one strange wasp came

October 2 and 3.-These days were cold; a few marked bees and wasps came to my honey, but no strangers.

October 4.-Two strangers.

October 6.-Only one stranger.

On these days the honey was watched almost with

out intermission the whole day, and was more or less regularly visited by the marked bees and wasps.

My experiments, then, in opposition to the statements of Huber and Dujardin, serve to show that wasps and bees do not in all cases convey to one another information as to food which they may have discovered, though I do not doubt that they often do so. Of course, when one wasp has discovered and is visiting a supply of syrup, others are apt to come too; but I believe that in many instances they merely follow one another. If they communicated the fact, considerable numbers would at once make their appearance; but I have not often found this to be the case. The frequent and regular visits which my wasps paid to the honey put out for them, prove that it was very much to their taste; yet few others made their appearance.

These and other observations of the same tendency seem to show that, even if wasps have the power of informing one another when they discover a store of good food, at any rate they do not habitually do so.

On the whole, wasps seem to me more clever in finding their way than bees. I tried wasps with the glass mentioned on p. 278, but they had no difficulty in finding their way out.

My wasps, though courageous, were always on the alert, and easily startled. It was, for instance, more difficult to paint them than the bees; nevertheless, though I tried them with a set of tuning-forks covering

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