oil HAY FEVER. 177 



plainer words, it poisons the already inflamed tissues of the 

 respiratory passages. No one doubts that, to some persons, skin- 

 poisoning is a certainty, upon walking on the lee-side of the toxic 

 SuiP.ach, RJins venenata^ in its flowering time. Why not then a 

 toxic eff"ect of pollen upon the mucous linings already super- 

 sensitive, and even lacerated by their presence ? 



In the old herbals the Solidago, as the word almost imj)lies, 

 had a reputation for vulnerable virtues, it bemg used in treating 

 wounds. One of the species, S. odorata, yields an aromatic oil 

 on distillation. It cannot, then, I think, be inert upon the surflice 

 of the inflamed and minutely lacerated mucous membrane. 



The laceration facilitates the poisoning. But there is another 

 possibility in this matter. The copious nasal secretions, acrid and 

 warm — have they no power for extracting the toxic principle ? 



4. — And, lastly, I am constrained to believe that pollen, in 

 ylCstivis, is a vital automaton — that it can, as a living organism, 

 perforate the mucous lining, actuated on the principle of a 

 pseudo-instinct ; not altogether unlike the Carrion-fly, when it 

 deposits its eggs, by mistake, on the decaying, nitrogenous 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 tlie "how" lies the "why?" 

 And occasionally we find a change of habit in an individual 

 plant, as left-handedness is found among rational beings. 



I must be permitted now to deal with some elementary ideas 

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

 the several pollens herein described, each must be regarded as a 

 highly-organised 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 

 fertilise 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 

 New .Series. Vol. I. N 



