Flowers and insects. XIV. 
CHARLES ROBERTSON. 
GENTIANA PUBERULA Michx.—From the abundant observ- 
ations on European species of Gentiana it appears that most 
of the species which have been investigated are proterandrous, 
though several are homogamous and a few proterogynous. 
Most of them are adapted to bumblebees, many to Lepidop- 
tera, while quite a number are intermediate, being visited by 
both kinds of insects. One species, G. /u¢ea, has exposed 
nectar, and is visited by a miscellaneous list. Nothing has 
been done with our species, except G. crintta and Andrew- 
Sit, 
In the case of G. Andrewsiz, Beal (6) observed that it was 
visited by bumblebees, but overlooked the proterandry, sup- 
posing that cross-pollination was favored by the stigma stand- 
ing far above the anthers. A statement of Meehan, that the 
flower never opens, evidently taking it for granted that it is 
never visited by insects, is quoted by Henslow (12) in spite 
of Beal’s observations. Vausenburg (10) objects to Beal’s con- 
Clusions, and supposes that the stigma is pollinated as it 
Passes the anthers. Kunze (18) regards the flower as cleis- 
togamous, the nectar being of no significance. Bailey (17) 
records that nectar is secreted by the walls of the corolla. 
Gray (19, 21, 25) states that the flower opens a short time 
in sunshine, which I have never observed; notes the proter- 
andry and that spontaneous self-pollination may finally occur 
by the lobes of the stigma curling back until they touch the 
anthers. Finally I have shown the adaptation to bumblebees 
and have recorded the abundant visits of Bombus american- 
orum F. £98(41). According to Beal (6) G. crinzéa is visited 
by bumblebees and resembles G. Andrewsii, of which, how- 
one , as we have noted, he had failed to recognize the proter- 
andry. 
_ G. Andrewsii and puberula, the only species I have found 
in my neighborhood, are the very latest of the bumblebee 
flowers, the former beginning to bloom by September 14th, and 
the latter on the 2 7th, both running nearly through October. 
Gentiana puberula has the stem terminated by a cluster of 
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