71 
Abnormal Flowers.— Mrs. C. T. Tracy sends to us from Ripon, 
Wis,, a sketch and description of a flower of Trillium cernuum^ L., 
which has one petal and two sepals of the ordinary form and color, 
while the third sepal has been replaced by a perfect leaf, and the 
other two petals have a green stripe through the centre. Mrs. Tracy 
says : ' A member of my botany class found a flower of Sanguinaria 
Canadensis with tw^enty-five petals, and a corresponding diminution 
of stamens. It was found among others that were in normal con- 
dition." 
Botanical Notes. 
On the Relation of Heat to the Sexes of Flowers.^ Ki a meeting 
of the Botanical Section of the Philadelphia Academy of Natural 
Science, on April 9, Mr. Thomas Meehan referred to his past com- 
munications to the Academy, showing that in monoecious plants 
female flowers would remain at rest under a temperature which was 
sufficient to excite the male flowers to active development. Hence a 
few comparatively warm days in winter or early spring would bring 
the male flowers to maturity, while the female flowers remained to 
advance only under a higher and more constant temperature. \n 
this manner the explanation was offered why such trees were often 
barren. The male flowers disappeared before the females opened, 
a-nd the latter were unfertilized. He referred especially to some 
branches of Cqrylus Avei/ana, the English hazle-nut, which he exhib- 
ited before the" Section last spring, in which the male flowers (cat- 
kins) were past maturity, the anthers having opened and discharged 
their pollen, and the catkins crumbling under a light touch, but 
there were no appearances of action in the female flower-buds. 
There were no nuts on this tree last season. The present season 
was one of unusually low temperature. There had not been spas- 
modic warmth enough to bring forward the particularly excitable 
maple-tree blossoms. The hazle-nut had not, therefore, had its male 
blossoms brought prematurely forward. He exhibited specimens 
from the same tree as last season, showing the catkins in a young 
condition of development, only half the flowers showing their an- 
thers, while the female flower-buds had their pretty purple stigmas 
protruding from nearly all of them. 
Mr. Meehan remarked that his observations the past few seasons 
had been so carefully made that he hardly regarded confirmation 
necessary, but believed the further exhibition of these specimens 
n^ight at least serve to draw renewed attention to his former com- 
r 
llustrations of British Fuuc^i.— American subscribers to 
this work will regret to be informed that the premises of the plate- 
printers were recently destroyed by fire, and, with them, all the work 
|n progress, including Part xviii. of the " Illustrations," which had 
just been completed. This will cause uncertain and unavoidable 
delay, but, as soon as possible, some arrangement will be made to 
continue the works on fungi and fresh-water algae. 
niunications. 
