RL pe eee eas Ee ae an a ee a tee ne Pye) ten ih ee etre) ae. ee ee ee AD van en Tae 
1878. | Glandular Hairs of Plants. 273 
tapering hairs composed of a single row of cells. Many species 
of Helianthus are covered with similar hairs. The surface of 
Panicum capillare, old witch grass, is covered with slender, one- 
celled hairs which are straight and quite stiff for their size. The 
surface of a common Physalis, or ground cherry, abounds in 
slender hairs composed of from ten to fifteen cells 
placed in a single row. Some of these hairs termi- 
nate in a sharp point, but most of them have, at the 
end, a round cell like a knob, full of a sticky sub- 
stance. Occasionally a hair 
produces one or more E p7 
branches which may like- } 
wise terminate with a short 
point or a globular cell. 
The fruit of Circea luteti- 
ana, enchanter’s nightshade, 
is covered with rather stout 
one-celled hairs which have 
a hook ‘at the extremity. 
The stems of the common Fic. 8. Fic. 9. BAG. 10. 
butter bean of our gardens ‘Hairs on surface of Physalis, ground cherry. 
have a few scattering hairs of similar structure, though they are 
_ smaller and much more delicate. 
The surface of Malva rotundi- 
Jolia, common mallow, is quite 3 
harsh to the touch on account of % 
numerous rather stout one-celled 
Fic. 11.—Hooked hair on fruit of 
Circea goe 
_ These stout hairs spread in every dakon Among the hairs 
Fig. 12. FIG. 13. 
Hairs on Maiva rotundifolia. Sessile gland on same plant. 
are a few sessile glands capped with two quarters of spheres. 
