On the Structure and Development of the 
Bulb in Laminaria bulbosa, Lamour. 
BY 
C. A. BARBER, B.A., 
Scholar of Christ's College, Cambridge. 
With Plates V and VI. 
Historical Introduction. 
I N the proceedings of the Cambridge Philosophical Society 
for 1885 Mr. Walter Gardiner drew attention to the fact 
that Laminaria bulbosa bears 6 sporangia upon its roots/ It was 
his intention at that time to describe the development of these 
so-called 6 roots, 5 and material was collected for the purpose 1 . 
The specimens have, however, remained untouched, and Mr/ 
Gardiner has placed them in my hands for description. 
The Laminaria in question differs from others of the genus 
in the development of the peculiar bulbous enlargement at the 
base, from which it derives its name 2 . It further possesses a 
flat stalk twisted once or twice at the base, while the lamina 
resembles that of L. digitata. The plant has a fairly wide 
distribution, occurring in Norway, the Faroe Islands, and on 
our coasts generally. According to Agardh, it extends along 
the Atlantic shores from Norway to Guinea. It is especially 
abundant in Cornwall and the Scilly Isles, where it is exten- 
sively used for manure. In spite of this abundance, and its 
marked characters, it was not successfully separated from 
1 In March, 1885, near Penzance. 2 Huds. Flor. AngL, 1778. 
[Annals of Botany, Vol. III. Mo. IX. February 1889.] 
