NEWS OF SPRING 



open. Then, when the fertilization is accomplished, the air 

 in the bladder is replaced by a mucilaginous fluid, heavier 

 than the water, and the whole apparatus sinks back again to 

 the slime in which the fruits will ripen. 



The method of the Utricularia is even more complicated. 

 M. Henri Bocquillon describes it in his Vie des Plantes: 



**These plants, which are common in ponds, ditches, pools 

 and the puddles of peat-bogs, are not visible in winter, when 

 they lie on the mud. Their long, slim, trailing stalk is fur- 

 nished with leaves reduced to ramified filaments. At the axilla 

 of the leaves thus transformed, we see a sort of little pyriform 

 pocket with an aperture at its pointed upper end. This aper- 

 ture has a valve, which can be opened only from the outside 

 inwards; its edges are provided with ramified hairs; the inside 

 of the pocket is covered with other little secretory hairs which 

 give it the appearance of velvet. When the moment of efflo- 

 rescence has come, the axillary utricles fill with air: the more 

 this air tends to escape, the more tightly it closes the valve. 

 The result is that it imparts a great specific buoyancy to the 

 plant and carries it to the surface of the water. Not 

 till then do those charming little yellow flowers come into 



[36] 



