129 



dicular. An egg of Simblum "aimed" horizontal shortly be- 

 fore its rupture gave rise to a horizontal mature fructification. 

 The absence of geotropism seems to substantiate the view that 

 the elongation of the stipe of the Phalloidei is an essentially dif- 

 ferent process from ordinary growth. 



Extrusion of the Gametes of Fucus. — As is well known, the 

 the gametes of Fucus are extruded from the conceptacles during 

 low tide, while the plants are out of water. It has been sug- 

 gested that the cause of their exit might be the removal of the 

 pressure of the water. But this pressure, even at high tide, is 

 insignificant. In reality, the Fucus plants shrink very appreciably 

 during low tide. As they begin to dry, the outer layers lose 

 some of the great amount of water which they hold by imbibition, 

 and their consequent contraction compresses the inner layers. 

 The pressure thus exerted against the conceptacles forces out a 

 part of their water content, carrying along the gametes, usually 

 before they separate from one another. Pinching a fruiting tip 

 between the fingers has the same result. As Strasburger sug- 

 gests (Praktikum, 296, 2d ed.), active gametes may be ob- 

 tained for study at a distance from the coast, and are extruded 

 when plants are removed from their vessel of sea water and al- 

 lowed to dry for a few hours. Instead of having sea water 

 shipped, I have made it for use at West Virginia University; it 

 need not be at all accurately made. The development of the 

 conceptacles and fruiting organs of Ascopliyllum seems to be 

 hastened by keeping the plants constantly submerged in standing 

 water. 



Adaptations of Spartiua polystacliya to Environment. — Spartina 

 polystacliya Willd. is the characteristic plant of the lowest tide- 

 water zone inside the bar of Cold Spring Harbor. The lowest 

 scattered plants grow where the tide leaves them from 3 to 3.5 

 hours. The lowest patches are left for about 4 hours. The 

 best development, both in density and height comes where the 

 ground is above water nearly half of the time. Near high tide 

 mark the plant disappears again. Young plants then spend 

 from one-quarter to three-quarters of their time submerged, and 

 it may therefore be assumed that immersion for some hours does 



