352 GLANDULAR HAIRS, Cuap. XV. 
in amount; but one such mass retained exactly the same form as 
before after an interval of 5 hrs.,so that it could hardly have 
consisted of living protoplasm. These glands seem to have very 
little or no power of absorption, certainly much less than those 
of the foregoing plants. : 
Mirabilis longiflora.—The stems and both surfaces of the 
leaves bear viscid hairs. Young plants, from 12 to 18 inches 
in height in my greenhouse, caught so many minute Diptera, 
Coleoptera, and larve, that they were quite dusted with them. 
The hairs are short, of unequal lengths, formed of a single row 
of cells, surmounted by an enlarged cell which secretes viscid 
matter. These terminal cells or glands contain granules and 
often globules of granular matter. Within a gland which had 
caught a small insect, one such mass was observed to undergo 
incessant changes of form, with the occasional appearance of 
vacuoles. But I do not believe that this protoplasm had been 
generated by matter absorbed from the dead insect; for, 
on comparing several glands which had and had not caught 
insects, not a shade of difference could be perceived between 
them, and they all contained fine granular matter. A piece of 
leaf was immersed for 24 hrs. in a solution of one part of car- 
bonate of ammonia to 218 of water, but the hairs seemed very 
little affected by it, excepting that perhaps the glands were 
rendered rather more opaque. In the leaf itself, however, the 
grains of chlorophyll near the cut surfaces had run together, 
or become aggregated. Nor were the glands on another leaf, 
after an immersion for 24 hrs. in an infusion of raw meat, in 
the least affected; but the protoplasm lining the cells of the 
pedicels had shrunk greatly from the walls. This latter effect 
may have been due to exosmose, as the infusion was strong. 
We may, therefore, conclude that the glands of this plant either 
have no power of absorption or that the protoplasm which they 
contain is not acted on by a solution of carbonate of ammonia 
(and this seems scarcely credible) or by an infusion of meat. 
Nicotiana tabacum.—This plant is covered with innumerable 
hairs of unequal lengths, which catch many minute insects, 
The pedicels of the hairs are divided by transverse partitions, 
and the secreting glands are formed of many cells, containing 
greenish matter with little globules of sume substance. Leaves 
were left in an infusion of raw meat and in water for 26 hrs., 
but presented no difference. Some of these same leaves 
were then left for above 2 hrs. in a solution of carbonate of 
ammonia, but no effect was produced. I regret that other 
experiments were not tried with more care, as M. Schlocsing 
