1905] CURRENT LITERATURE 69 
it appears that PLATEAU’s views have become less positive; he held at first that 
color and form have no influence in mapa insects to flowers. At present, 
while all color preference is denied, and while odor and the presence ti a 
are believed to be the most potent attractive agents, he seems not to deny altogether 
the possibility of color attraction. PLATEAU’s work has been accepted by but 
few students of flower ecology, and has been violently attacked especially by 
Krenitz-GEeRLorr.4 P£REz,5 while not calling PLATEAU’S results in question, 
+ thinks that his conclusions are too one-sided. He holds that odor attracts at a 
} distance, but that color serves to give directional precision close at hand. Forr® 
} thinks that PLareau and other authors have given insufficient attention to the 
memory sense of insects. 
The immediate occasion for this review is the work of ANDREAE? and Griray.® 
_ ANDREAE begins his admirable treatise with the rather teleological statement 
‘ that it is inconceivable that there should be so many showy flowers in the world, 
~ kunless they are of some value to the plant, and that we cannot conceive of any 
-}-use other than the attraction of insects! As the result of a great many ingenious 
g experiments, he divides insects into two genera! groups: those with weak visual 
sense, short flight, and high odor sense; and those with opposite characters. 
in particular, includes the Apidae and the higher Diptera. Thus, while many 
insects are attracted chiefly by odor, the bees and the higher flies are attracted 
chiefly by color. Bees tried to get inside of inverted glass vessels with flowers 
inside, while they paid little attention to open vessels with honey or perfume. 
A very gaudy artificial poppy had more visits than natural and less showy flowers, 
although it was observed that the insects soon learned to visit non-showy flowers 
containing honey and to avoid showy flowers that had no honey. Since the 
perception of odor is highly modified by direction of wind, moisture, and the 
| presence of other odors, ANDREAE thinks that color is a much more reliable and 
_ f effective attractive agent than odor. 
The memory sense, touched upon by Foret and ANDREAE, has been the 
special! thesis for GILTAy’s work, and his work seems to harmonize the discord- 
ant results of PLATEAU and ANDREAE. A new line of experimentation is sug- 
gested by his work on Papaver Rhoeas, a species whose flowers are self-sterile; 
from one group the petals were removed and the flowers left free for insect visita- 
tion, another group was left in the normal condition and free for insect visitation, 
hie 
. 
EE necator cag plea She Ri 
4See Bot. Zeit. 54:123; 55:84; 55:108; 56:138; Biol. Cent. 18:417; 23:557. 
5 See Act. Linn. Soc. Bordeaux, 1896; Mém. Soc. Sci. Phys. Nat. Bordeaux, 1903. 
6 See Zool. Jahresb. t1gor. 
7 ANDREAE, E., Inwiefern werden Insekten durch Farbe und Duft der Blumen 
“@ angezogen? Beihefte Bot. Cent. 15:427-470. 1903. 
a 8 Gittay, E.: Ueber die Bedeutung der Krone bei be Bliiten und iiber el 
z ee ecto Sereno der Insekten. I. Jahrb. Wiss. Bot. 40: 368-402. 
~ 1904. 
