favourable conditions on damp sand; other seeds of the same lot being tried at the same time in the same manner, and found to germinate well.  Of the seven seeds which had been exposed to the secretion, only three germinated; and one of the three seedlings soon perished, the tip of its radicle being from the first decayed, and the edges of its cotyledons of a dark brown colour; so that altogether five out of the seven seeds ultimately perished.

Radish seeds (Raphanus sativus) of the previous year were placed on three leaves, which became moderately inflected, and re-expanded on the third or fourth day.  Two of these seeds were transferred to damp sand; only one germinated, and that very slowly.  This seedling had an extremely short, crooked, diseased, radicle, with no absorbent hairs; and the cotyledons were oddly mottled with purple, with the edges blackened and partly withered.

Cress seeds (Lepidum sativum) of the previous year were placed on four leaves; two of these next morning were moderately and two strongly inflected, and remained so for four, five, and even six days.  Soon after these seeds were placed on the leaves and had become damp, they secreted in the usual manner a layer of tenacious mucus; and to ascertain whether it was the absorption of this substance by the glands which caused so much inflection, two seeds were put into water, and as much of the mucus as possible scraped off.  They were then placed on leaves, which became very strongly inflected in the course of 3 hrs., and were still closely inflected on the third day; so that it evidently was not the mucus which excited so [page 128] much inflection; on the contrary, this served to a certain extent as a protection to the seeds.  Two of the six seeds germinated whilst still lying on the leaves, but the seedlings, when transferred to damp sand, soon died; of the other four seeds, only one germinated.

Two seeds of mustard (Sinapis nigra), two of celery (Apium graveolens)—­both of the previous year, two seeds well soaked of caraway (Carum carui), and two of wheat, did not excite the leaves more than inorganic objects often do.  Five seeds, hardly ripe, of a buttercup (Ranunculus), and two fresh seeds of Anemone nemorosa, induced only a little more effect.  On the other hand, four seeds, perhaps not quite ripe, of Carex sylvatica caused the leaves on which they were placed to be very strongly inflected; and these only began to re-expand on the third day, one remaining inflected for seven days.

It follows from these few facts that different kinds of seeds excite the leaves in very different degrees; whether this is solely due to the nature of their coats is not clear.  In the case of the cress seeds, the partial removal of the layer of mucus hastened the inflection of the tentacles.  Whenever the leaves remain inflected during several days over seeds, it is clear that they absorb some matter from them.  That the secretion penetrates their coats is also