368 THE AMERICAN NATURALIST.  [Vor. XXXIV. 
smallest clump of flowers one or more of these skippers sitting 
in the position shown in Pl. I, Fig. 2, far from anther and 
stigma, stealing the nectar. They get it with some difficulty, 
to be sure, the holes opening into the nectary not being visible 
from the outside. They must stand outside and insert the pro- 
boscis obliquely between the sepal and the base of the style, 
plying and thrusting with it until a hole is found. Repeated 
trials occasion loss of time, and when the hole is found not all 
the nectar adjacent to it can be reached from one position. 
Nevertheless, one cannot witness the persistences of the skip- 
pers, and their abundance throughout the season, without 
being convinced that they get a large share of the nectar. 
Very interesting as bearing on the validity of long-accepted 
theories of floral coloration (which some are nowadays saying 
were accepted without sufficient experimental proof) are the 
habits of the pamphilas in visiting the flowers. When the 
question is raised, Do the guide streaks really guide? the pam- 
philas on the blue flags will furnish affirmative evidence. Fig. 
3 shows a flower as seen from above. The center of the 
flower is at the deepest point between the divisions of the 
style, and the lines of these divisions all point toward the cen- 
ter, analogously to the guide streaks on the corolla of Convol- 
vulus. There are special guide streaks, to be sure, at the proper 
points of entrance; but these are in unusual places and are also 
arranged radiately about the center of the flower. Pamphilas vis- 
iting the flowers habitually try to enter at the center. One will 
roam over the summit of the flower, returning to try for en- 
trance at the central cleft, again and again. When one has 
strayed to the end of the style branch and stumbled upon the 
right entrance, it will generally be seen to try for a moment to 
enter there. After several ineffectual attempts at the center, it 
will pass over the edge of the sepal and descend backward or 
sidewise to the position shown in the plate (Fig. 4). That 
something similar was observed by Professor Charles Robert- 
son is indicated by the two words which I have underscored in 
the following quotation: * Sometimes butterflies obtain nectar 
in an illegitimate way, by backing down to the base of the 
flower and inserting their proboscides between the bases of the 
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