26 BULLETIN 137, U. S. DEPARTMENT OF AGRICULTURE. . 
such varieties does not come about through the breaking of that 
organ, but by its being loosened from the glume. It is the tissues of 
the glume that give way, and lack of persistence is thus in reality a 
character of that organ. 
In the hooded barleys the awn of the flowering glume is replaced 
by a trifurcate appendage. This is of evident monstrous origin and 
is connected with the awned class by no true intermediates. The 
exact nature of the appendage is not clear. In structure the parts 
appear to be the result of vegetative stimulation, and they are glume- 
like in appearance. The fact that they are three in number and that 
they bear rudimentary florets indicates that they are a partial repeti- 
tion of the spikelets of an internode, the leafy segments being the 
flowering glumes. The character is absolutely constant. 
THE BASE OF THE FLOWERING GLUME. 
The method of the attachment of the lemma, or flowering glume, 
to the rachis has been shown by Atterberg (1) to be a distinguishing 
mark between the erectum and nutans groups. In the nutans group 
the grain (and therefore the flowering glume) is attached by a very 
constricted band of tissue which, when separated, leaves the proximal 
extremity smooth. The surface is oblique to the long axis of the 
grain and presents a small horseshoe-shaped depression just above 
the line of attachment. In the erectum group there is more than one 
variation of form, but all are centered around an attachment to the 
rachis that is much broader than in nutans and the depression is 
absent. When the central nerve of the dorsal glume is not too large 
and continued too far through the base, a transverse crease is found 
just above the attachment. The 6-rowed barleys are separated by 
the same means. 
ADHERENCE OF THE FLOWERING GLUME TO THE PERICARP. 
The normal form of barley is one in which the glumes are grown 
fast to the pericarp. There are numerous varieties in which this 
union does not occur. These constitute our naked barleys. Both 
forms are absolutely stable. The character offers no opportunity for 
minor distinctions, unless it be in such cases as Princess, which the 
Swedish Plant- Breeding Association maintains has a low weight per 
bushel, owing to an abnormally loose attachment of the glumes. 
THE SVALOF CHARACTERS. 
In 1889, Neergaard (19), of the Swedish Plant-Breeding Associa- 
tion at Svalof , announced the most important discovery in the classi- 
fication of the lesser groups of barley that has ever been brought to 
the attention of the world. Not only was it of exceptional intrinsic 
value, but it acted as a great stimulus in the study of elementary 
