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organs) from the conceptacles, is accomplished by mechanical 

 pressure which is developed within the plant, whether the plant 

 dries and contracts or not. I fancy the same thing is true of the 

 other species of Funis on this coast, and also of the species on 

 the Atlantic Coast, including the unnamed one about which Dr. 

 Copeland writes. It is obvious, however, that the drying, con- 

 traction, and compression, of which Dr. Copeland speaks, will 

 supplement the pressure which normally develops within the 

 plant itself. 



Where Fucus grows in thick masses covering the rocks 

 between tide-marks, only those plants living far up on the sides 

 and on the tops of rocks will have any considerable part directly 

 exposed to the air and sun. When the tide goes out, a very 

 small part of a mass of Funis is wholly exposed, as the fronds 

 overlie and protect one another, only the topmost layer being 

 wholly uncovered. Of course the overlapping is more or less 

 incomplete, so that some of the tips of the plants below may be 

 exposed. These exposed tips and whole plants represent, how- 

 ever, only a small proportion of all the fruiting parts. These 

 exposed parts are the only ones which would dry and contract 

 in such a way as to expel the reproductive organs and elements, 

 and yet other plants and other tips are undoubtedly also fertile, 

 in the fullest sense of the word. 



Again, the amount of drying, contraction and consequent 

 forcing out of the reproductive parts when low tide comes at 

 night would be very slight. Are such tides unfavorable to re- 

 production ? Then, too, there is little or no drying of Funis or 

 anything else in fog or rain. At these times, too, the gametes, it 

 ripe, should be forced out of the conceptacles. 



I think I have shown the desirability of the plants' possessing 

 some adequate means of removing the gametes from the con- 

 ceptacles no matter what the weather, the time of day and the 

 state of the tide may be. Unfortunately I cannot prove that the 

 Atlantic * species of Funis are in this respect as independent of 



' [There are at least three very distinct species of Fucus about New York City : a 

 hermaphrodite species (F. spiralis ~L. ?) found only near the h igh- water mark ; a 

 dioecious species ( F. vesiculosus L. ) of rather wide range in the littoral zone ; and a 

 hermaphrodite species {F. evancscens Ag. ) growing near the low-tide line and in 



