Plate XVni. 



Alaria cramfolia K-TEiiLM. 



Fii>;s. 1-3. Gaïuetopliytes foimd iu uatiire ; simple aud sterile, branched and 

 antlieridial, and branelied and oogonial, respectively. x 450. 



rij:ïs. 4-5. Sporeliugs with unicelhüar rhizoids. x 450. 



Figs. 6-7. Monostromatic emlnyonal blades to show the cellular arrangement. 

 At the stage shown in Fig. 6 the cells are still disposed iu the 

 hyperl)oli(^ ügnre as has been observed in a similar stage of 

 Cofitaria Tarneri. x450. 



Figs. 8-11. Mucilage glands observed at a post-emb ,'t)nal frond of al^out 

 15 cm. in total height. Fig. 8, surface v -w of a marginal part 

 of the frond at about 5 cm. above the f ausitio i region. The 

 glands are denser and smaller along le margin, rarer and 

 larger towards the midrib, and finally ei] irely absent. Beyond 

 the area here delineated no gland could be seen. The glands 

 near the transition region are colomless and gTanular, those at 

 3-4 cm. above the transition region and upwards gain darker 

 l)rownish hue. . x 54. Fig. 9, A part of the same enlarged. 

 The epidermal cells overlj'ing the glands are seldom disposed 

 radiately around a gland, x 450. Fig. 10, cross section of the 

 blade at the same point. x450. Fig. 11, smface view of an 

 upper part of the blade ^\ith the four glands fused together but 

 still with the septal membranes between them, x 450. 



Figs. 12-14. DiagTamatic figures of the cross sections of the basfd cjdindrical 

 part and the complanated part of the stipe, and the midrib 

 respectively, of a two-year old plant. About x 10. a, epidermal 

 layer (limiting layer of Setchell) ; b, second year cortex ; c, 

 outer cortex ccjmposed of radially disp jsed cells ; d, inner cortex 

 composed of larger parenchymatic celh; e, perimediillary tissue ; 

 /, medullary sheath ; g, medulla ; h, marginal swelling of the 

 medulla ; /;, spanning cortex. 



Fig. 15. Part of a cross section of the midril) of a matured frond, to show 

 the compact tissue of the medullary sheath about the marginal 

 s^\'elling of the medulla ; e, perimedullary tissue ; /, medullary 

 sheath ; d, inner cortex, x 240. 



Fig. H). Part of a cross section of the midrib oi a matured frond, a point 

 aI)out the median line, stained iu an aqueous solution of anilin 

 blue. The cell-wall of the inner cortex and the liyphte stain 

 very pale, those of the perimedullary tissue deep blue, and the 

 callus of the trumpet cells in the medulla deepest, x 240. 



Fig. 17-18. Two trumpet cells ; Fig. 15, thick-Avalled cells, treated fii'st in 

 sulphuric acid and then in chloriodide of zinc. Fig. 16, callus 

 formation, stained in an aqueous solution of anilin blue, x 450. 



