1906] SIMONS—SARGASSUM FILIPENDULA 167 
sists of a more or less homogeneous ground substance and one or more 
refractive areas which are somewhat centrally placed. The modified 
structures vary from spheres, whose ground substance has been 
changed only at the periphery, to swollen masses which have an 
entirely modified ground substance with an irregular outline. Both the 
intact and modified bodies may occur within the same cell; but the 
former and the least modified are more common in epidermal cells, 
whereas the most modified are in cortical cells. The occurrence of 
such bodies within epidermal cells where photosynthesis is the most 
active, suggests that they represent a manufactured food. The varied 
modifications in the structures indicate the solvent action of the killing 
fluid, or an intercellular enzyme. As the inner cells contain bodies 
presenting greater modifications than the epidermal cells, the agent 
producing the change is apparently applied from within the tissue. If 
then within, it is probably an enzyme, for a solvent used in the process 
of killing would attack the contents of epidermal cells, doubtless before 
any others. The intact bodies may represent a newly formed product, 
perhaps a carbohydrate, and the modified structures, the product in 
process of digestion. ‘The bodies do not stand with iodin in any con- 
dition. If they are carbohydrate they probably differ as much or 
more from the starch of higher plants as does inulin. The presence of 
many small spheres in formalin material and their absence from tissues 
preserved in alcohol indicates that oil globules are present in the cell, 
in addition to the structures described above. Future investigations 
on living material will probably disclose the presence of both oi 
and a carbohydrate in the Phaeophyceae. 
THE ORIGIN AND DEVELOPMENT OF THE CONCEPTACLE,. 
The conceptacle in the Fucaceae had been but little studied when 
Bower (’80) gave an account of its development in four genera 
and six species (Fucus serratus, F. platycarpus, F. vesiculosus, Ozon- 
thallia nodosa, Halidrys siliquosa, and Himanthalia lorea). Accord- 
ing to him the development of the conceptacle in every species con- 
forms to one scheme with minor variations. 
The “‘initial cell’? of the conceptacle, as stated by Bower, is the 
terminal cell of a linear series which is produced by a modification of 
the regular divisions in the segments of the apical cell of a receptacle. 
