316 REPORT OF THE CONFERENCE ON GENETICS. 
the improvement of the sugar-cane by hybridisation has made wonderful 
strides, and now experiments, conducted on scientific lines, are being 
carried out in Java, India, Hawaii, Queensland, Cuba, British West Indies 
and British Guiana, &c., with the hope of raising canes less susceptible 
to disease, and yielding a larger amount of sugar per acre. 
DESCRIPTION OF FLOWER. 
Before dealing with the different methods of obtaining hybrids it may 
be advisable to give a description of the flower of the sugar-cane. The 
flower has often been described and figured, while good descriptions of 
the seed and its germination were given by Benecke in the “ Bulletin of the 
Middle Java Experiment Station,’ 1889, and also by Morris in the 
“ Journal of the Linnean Society,’’ 1890. 
The following description has been taken from notes made from the 
examination of many hundred flowers of different varieties during 
hybridisation experiments at Barbados in 1905-6 :— 
The inflorescence or “arrow” varies from 2 ft. to 3 ft. in length. 
It is repeatedly branched, each branch bearing laterally a number of 
spikelets. The numerous spikelets are one-flowered and hermaphrodite, 
and are generally arranged in pairs, one being sessile and the other 
stalked, at distances of a little more than } in. on alternate sides of the 
slender, long branches. From the base of each spikelet, attached to the 
rachis, spring a large number of stiff, long, silky hairs, which give the 
inflorescence a glistening silky appearance in the sun. 
The “flower has the following formula: —Glumes, 2; palea, 1; 
lodicules, 2; stamens, 3; ovary, single; style, 1 (bifid). 
The two glumes are nearly equal; oblong-lanceolate, acute ; unawned ; 
stiff; at first green, then purplish, the intensity of which varies in 
different varieties. The lower is two-nerved and measures 2°5 to 3°6 mm. 
long, by 0'7 to 0°9 mm. wide. ‘The upper is distinctly one-ribbed, 
slightly keeled, and measures 2°8 to 3°8 mm. long, by 0°8 to 1:3 mm. 
wide. These measurements are the average of many investigations on 
different varieties, for whereas the size of the glumes is generally 
constant in any given variety, considerable variations have been observed 
between different varieties. 
The palea is solitary, thin, white, membranous, and is enclosed 
in the upper glume, than which it is slightly shorter. It is ovate- 
lanceolate, slightly obtuse, generally smooth, and apparently unveined. 
The two lodicules are free, minute, truncate or 2-3-lobed, and vary 
in colour from white to yellowish-green. 
The stamens are three in number (during hybridisation experiments 
in Barbados in 1905-6 three instances of four were found and noted). 
The anthers are linear-oblong, versatile, and vary in colour from yellow 
when young to a deep yellowish-red when mature. 
Ovary smooth, uni-carpellary ; style one, bifid. The styles vary con- 
siderably even in the same variety, for in some instances a single style 
springs from. the top of the ovary and soon becomes bifid, while in . 
others there are two styles distinct throughout. The stigmatic plumes 
are always two in number, and are large, densely plumose, and dark 
reddish-purple when mature. 
