46 
Barber. — On the Structure and 
External Form. 
In the earlier stages of development L. bidbosa appears to 
differ but slightly from other species of the genus. The 
youngest plant (Fig. i) with which I am provided consists of 
three parts — an oval expanded portion, the lamina, two inches 
long and one inch broad ; a short cylindrical stalk ; and this 
passes downwards into several rounded expansions which serve 
for the attachment of the young plant. At a short distance 
below the junction of the lamina and the stalk there is already 
developed the ridge which represents the commencement of 
the bulb. There is in this specimen a curious prothallus-like 
expansion attached to the stalk. This appears to be one of 
the attaching processes which, instead of becoming applied to 
the substratum, has grown up and almost fused with the 
stalk. 
The early development of many Algae has been patiently 
worked out by Stromfelt 1 . Unfortunately his short paper on 
the subject is without figures, and professes to be of the nature 
of a prefatory notice. Until the larger work with figures 
appears we must be content with such brief descriptions as he 
gives. Stromfelt divides the embryonic organs of fixation of 
Algae into three classes, according as they develope on ger- 
mination, — i. a primary root-cell; i. a creeping branched 
cell-row ; 3. a cushion-like cellular mass. After describing 
various lower Algae as falling under the second division he 
states that probably all the (Norwegian?) Phaeozoosporeae be- 
long to the same type. Of Laminaria, he writes thus : ‘ Lamin- 
aria shows in many points a close relation to the Phaeozoo- 
sporeae, and probably agrees with them in that it is developed 
from a simple cell-row ; but the organ of fixation undergoes so 
many changes during development that it deserves a separate 
notice. At first root-threads are developed, as for example in 
Chorda or Ilea, but here they remain unicellular and free. 
The basal portion of the shoot becomes rounded to form the 
stalk, and the lower part of this forms a thick basal bulb as a 
1 Bot. Centralblatt, xxxiii. 
