244 Ward. — On Relations between Host and Parasite 
The ‘ seed * of B. asper resembles that of B. erectus in 
general shape and size, but is heavier and more plump. It 
is somewhat cylindroid, measuring about io x i*5 mm., and 
with short awn (4-5 mm.), palea finely nerved and upper end 
ciliate. Rachilla somewhat long. 
The four-day seedlings of B. asper showed very slow 
germination, the radicle having only just appeared, the 
plumule not yet evident from between the pale thin yellow 
paleae. Awn short and fine. Outer palea flatter and thinner 
than in the B. sterilis type, and approaching the 1 boat type ’ 1 
of the Serrafalcus group. 
B. inermis, Leyss. 
Occurs in Europe, the Caucasus, and N. Asia. It is 
regarded as an important grass for very dry climates, its 
perennial creeping rhizomes enabling it to withstand the 
aridity of the Steppes and dry prairies. B. inermis is closely 
allied to the widely spread North American B. ciliatus , L., 
which may be regarded as its New World representative ; 
but although B. inermis is not a native of America, it grows 
well there — e. g. on the Pacific Coast — and has been widely 
introduced elsewhere, as the Hungarian or Awnless Brome. 
The ‘ seed * of B. inermis is much flattened ; and awnless 
or with a mere trace of awn. Size 10-12x2 mm. Lower 
palea flat, distinctly nerved above, margins curved in slightly 
below. Apex somewhat torn. Upper palea closely adherent 
to caryopsis. Rachilla short, about 2-5 mm., stiffly hairy, 
hardly projecting. Caryopsis 6-10 mm. long, very flat, 
slightly sinuous, acute at both ends, hairy above. Median 
ventral furrow very shallow ; hilum a mere ridge or keel 
owing to the adherent palea. ‘Seed 5 in the mass yellowish- 
grey. 
The ‘ seed ’ germinates fairly well, but slowly. Of 41 
‘seeds’ sown, only 13 germinated in five days, and on the 
sixth day the seedling was somewhat characteristic owing to 
the bluntly rounded, somewhat torn palea. 
1 See Marshall Ward, ‘ Grasses,’ pp. 127-128. 
