282 MIS& SARAH M. BAKER ON THE 
which it was attached to the clay bottom of the pools. In size the plant of 
Foslie was about the same as the normal attached Pelvetia. The habit of this 
‘ar. radicans seems to be somewhat similar to the coralline form at Blakeney, 
but does not correspond in all respects. The coralline Pelvetia was only very 
oceasionally found, possibly because the loose-lying form usually obscured it. 
Relations of the Free Form of Pelvetia with Salicornia.—The effect of the 
extensive matting of Pelvetia on the growth cf Salicornia іх well shown by a 
series of experiments, of which notes have been handed me by Prof. Oliver. 
On October 24, 1908, before the Salicornia had shed its seed, an area 
10 feet square was cleared of Pelvetia and staked, The Salicornia was left, 
and no doubt scattered its seed a few weeks later *. 
July 14, 1909. 
Staked area showed : 
1. Fewer plants within than outside—roughly about one-fifth. 
2. Plants within averaged 2-8 in. in height, those outside about 5 in. 
This difference in height became very evident when the tide rose, those 
without standing up 2 in. above the surface, while those within the area were 
entirely covered. 
November 6, 1909. 
Salicornia within sparser than without ; the plants were erect, whilst most 
of those outside, especially where they grew densely, were lying on their 
sides. 
About 100 plants were collected at random from within and without, and 
statistical determinations of the plants of the two batches were carried out as 
follows t :— 
Results. 
Without Pelvetia. With Pelvetia. 
| Average length.......... 14:07 cm. 17:97 em. 
|! Average Фашеег........ 440 mm. 4:53 mm. 
| Total wet weight........ 152 grms. 220 orms. 
| 
| Total dry weight ........ 33. 42 
n 
115 plants of each batch taken. 
* The area was just to the right of the large stranded smack ‘ Britannia,’ seen on the left 
of РІ. 8. fig. 1. 
t The measurements were made by Miss M. H. Bohling, of University College. 
