Ra?naley : observations on egregia menziesii. 7 



were observed between the structure of the proliferations of the 

 stipe and of the lamina. The gonidia-bearing proliferations 

 bear gonidangia over the whole surface on both sides and on 

 the edges. A small part of the broad blunt distal end is sterile. 

 The gonidangia and paraphyses have the usual structure for 

 members of the family as described by various observers. 



Meristem. — The merismatic region between the rachis and 

 lamina shows in its structure the same areas recognized in the 

 older parts. The cell cavities of the pith web are rather large 

 and become smaller with the mucilaginous thickening of the 

 walls. All the cells of the merismatic area are quite thin- 

 walled. 



Summary and conclusions. — The morphology of Egregia is 

 best understood if we consider it as an Alaria in which the 

 stipe is branched close to the holdfast and each branch has 

 taken on the characters of the entire shoot area of Alaria. In- 

 stead, however, of a few large proliferations of one kind borne 

 on the stipe, Egregia has hundreds or thousands of small pro- 

 liferations on both rachis and lamina. These proliferations are 

 of various shapes. The stalks of some are swollen and hollow, 

 forming air vesicles. These occur only on the rachis, never 

 on the lamina. The gonidia-bearing proliferations are always 

 small and rather cuneate in outline. Like the vesicles they are 

 confined to the rachis. The laminae are narrow and compara- 

 tively short, so the photosynthetic function develops chiefly on 

 the proliferations. It is properly to display these that the de- 

 velopment of vesicles has been necessary. 



Egregia agrees rather closely with other Laminariaceae in its 

 anatomy. The stipe, rachis and lamina all show the usual 

 areas, epidermal, hypodermal, cortical and medullary. The 

 thickenings of the rachis and lamina are irregular multicel- 

 lular emergences which in the lamina are above thickened 

 places of the medulla (pith web), but which in the rachis are 

 more superficial, consisting only of thickened areas of the other 

 layers. The pith web is present in the main stipe but not in 

 the branches of the holdfast. There is either no pith web in 

 the proliferations or it is poorly developed. All of the prolifera- 

 tions have the same anatomical characters. An abundance of 

 carbohydrate reserve material is usually present in the outer 

 cells of the proliferations and also of other parts of the plant. 

 In the structure of the gonidangia Egregia agrees with other 



