104 JOURNAL OF THE [April, 



fungus, instead of putrid flesh. If we are to understand by 

 instinct, "inherited experience," it is to be found even in plants. 

 It is true that we are told how the Hop twines to the left, and 

 the Scarlet-runner to the right, but back of the " how" lies the 

 " why ?" And occasionally we find a change of habit in an 

 individual plant, as left-handness is found among rational 

 beings. 



I must be permitted now to deal with some elementary ideas 

 on the subject of fertilization by the pollen-grain. In respect to 

 the several pollens herein described, each must be regarded as 

 a highly organized cell, with a twofold shell — an outer rind, 

 which is thick, and carries the armature of spines ; and an inner 

 one, which is thin, in fact, a membrane, which is exposed at the 

 surface in grooves, spots or pores, and these exposed places are 

 always smooth. In the Golden-rods, as shown in the figures, 

 these depressions are longitudinal grooves. The interior of the 

 pollen consists of a viscid life-stuff, or protoplasm, whose 

 function is to fertilize the ovule, at the base of the style in the 

 pistillate flower. To effect this a curious play of the life-force 

 sets in. The style is composed in part of a loose, or more or 

 less spongy tissue, while the stigma at the top is charged with 

 a saccharine, sticky mucilage. A pollen-grain, borne by the 

 wind, or an insect, usually, now falls upon the stigma, and is 

 anchored to it by the spines sinking into the gum. The moist- 

 ure causes the grain to swell. There is a protrusion of the 

 membrane at one or more of the thin places at the surface, 

 whence a tube, or root-like process emerges, and penetrates the 

 stigma. It seems to be an extension in tubular form of the 

 membrane, and is filled with the protoplasm of the cell. If the 

 kid-glove on a lady's hand could be pinched at the back, and 

 that nip of the glove pulled out or extended, and the flesh could 

 flow into this extemporized little pipe, it would roughly repre- 

 sent the pollen tube. Having pierced the outer coat of the 

 stigma, this tubule, by a sort of growth, keeps on lengthening, 

 and pushing its way down through the loose tissue of the style, 

 until it has reached the ovule at the base, when its mission 

 ends, and the future seed of that flower is assured. 



Now to return to my statement of mistaken instinct in the 

 insect. Pseudo-instinct is also found in plants, even in the 



