64 Barber. — On Laminaria bulbosa, Lamonr. 
DESCRIPTION OF FIGURES IN PLATES V AND VI 
Illustrating Mr. Barber’s paper on the Development of the Bulb in 
Laminaria bulbosa. 
Figs, i, 2, and 3. Young plants of L. bulbosa , showing the origin of the ridge 
from which the bulb is developed. Natural size. 
Fig. 4. Lower part of older plant, with bell-shaped organ of fixation developed 
from the ridge : the primary fixing organ is visible in the centre of the bell. 
Natural size. 
Fig. 5. Vertical section through bulb of an older specimen, showing the develop- 
ment of three successive circles of hapteres. Natural size. 
Fig. 6. A somewhat older bulb with numerous hapteres. Slightly reduced. 
Fig. 7. Ground-plan of the same viewed from below, showing the circles of 
hapteres developing in a centrifugal manner. The primary organ of fixation,^ 
is seen at the centre, and has fused with the innermost hapteres. 
Fig. 8. Plant of Z. bulbosa about two feet long. The furbelows are not yet 
developed. 
Fig. 9. Older bulb, from which the stalk and lamina have been torn, x 2 / 3 . 
Fig. 10. Part of an old bulb covered with tubercles. The whole is brown with 
sporangia. 
Fig. 11. Section through epidermis and cortex of stalk at ridge (same specimen 
as in Fig. 19). 
Fig. 12. A portion of the medulla of the stalk above the ridge (of the same 
specimen), in longitudinal section. The walls of the cells have become thickened, 
and hypha-like protrusions are being sent into the thickness of the walls. 
Fig. 13. Portion of the medulla in the transverse section of the lamina (specimen 
in Fig. 8). 
Fig. 14. The formation of a hyphal protrusion from a single cell of the same. 
Fig. 15. Longitudinal section through stalk of same specimen. Some of the 
cortical cells near the medulla are figured : only a part of the two large tubes 
is shown. 
Fig. 16. Hyphal cell with many nuclei ; obtained from specimen in Fig. 3 in a 
transverse section through the stalk at the ridge. This section is stained with 
haematoxylin, and was cut, like most of the others, in paraffin by the microtome. 
The hyphal cell passes out at right angles to the stalk into the developing ridge. 
Fig. 17. Cell with many nuclei and chromatophores ; one of the large cells in 
the cortex of Fig. 19. 
Fig. 18. Cells of medulla below the ridge; from a very young specimen 
(Fig. 1). 
Fig. 19. Longitudinal section through a stalk at the ridge ; from a slightly older 
specimen. 
Fig. 20. Cells from the transverse section of a haptere ; the haptere was taken 
from specimen in Fig. 6. 
Fig. 21. Longitudinal section through the apex of an attached haptere with 
rhizoids : the haptere was taken from the same plant. 
Fig. 22. Section through epidermis of bulb represented in Fig. io, showing 
sporangia and paraphyses. The sporangia are unilocular. * 
Fig. 23. Copied roughly from figure of Harvey’s in Mrs. Gatty’s British Sea- 
weeds. Supposed to represent an old plant of Z. bulbosa. 
