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to say or to imply more than that the escape of the reproductive 

 elements is hastened by the drying and contraction of the fertile 

 fronds when they are exposed to the air. Unless I do Dr. Cope- 

 land an injustice, he does imply that their escape is effected by 

 the shrinkage of the parts. On this point I wish to state my own 

 experience. 



Last summer and the summer before, at the Hopkins Seaside 

 Laboratory, Pacific Grove, California, I repeatedly put the fruit- 

 ing tips of Fueus evanescens Ag., into glass dishes of sea-water 

 and left them, often for two weeks, without changing the water 

 or baring the plants. The gametes escaped nevertheless, spores 

 and young plants of various ages presently appearing on the 

 bottom of the dishes. In this way I was able to get a series of 

 young plants consisting of from one to many cells. 



In these cases, neither water-pressure nor the compression of 

 the parts within by the drying and contraction of the outer parts, 

 can have had anything to do with the escape of the spores. 

 Another factor was concerned, namely, the solution of the gel- 

 atinized walls and other gelatinous material surrounding the 

 gametes. When this goes into solution, the antherozoids can 

 swim out of the conceptacles. This does not, however, account 

 for the escape of the non-motile egg-cells. It will be noticed 

 that the fruiting tips of this species of Fiiciis are covered with 

 gelatinous drops, a drop at the mouth of each conceptacle, 

 whether the plants are submerged or exposed. The drops ooze 

 out, that is are squeezed out, from the cavity of the conceptacles. 

 The expressed slime may become so abundant as to form a coat- 

 ing over the surface of the fruiting tip. The pressure which 

 forces this out is developed by the parts surrounding the con- 

 ceptacle and first becomes effective when the antherozoids and 

 egg-cells, or the antheridia and oogonia, become detached and 

 are imbedded in a gradually dissolving gelatinous matrix. As 

 this gelatinous material dissolves, it resists the compressing effect 

 of the walls of the conceptacle less and less, and presently becomes 

 squeezed out through the mouth of the conceptacle. 



So far as this species of Fucits is concerned, therefore, the 

 extrusion of the gametes (or, more properly, of the sexual 



