Grinnellia americana , Harv. 
25 
of highly refractive, yellow cells at the base of the procarpium. 
It differs in that the pericarp is only two to three layers of 
cells in thickness, and that no fusion of cells is observed in the 
basal cystocarpic region of Grinnellia. As previously stated, 
this is one of the most salient points developed in the study 
of Grinnellia. This subject was more interesting, and received 
more special attention, because fusion of cells in the basal 
cystocarpic region had been reported for other Florideae, 
notably the closely related genus Gracilaria. 
1 6. It is perfectly evident that fusion of cells in the basal 
region of the developing cystocarp does not occur ; but that 
the large amount of nourishment supplied to the ooblastema- 
filaments by the cells growing directly from the joint-cell at 
the base of the cystocarp, is received directly through the pits 
from the group of densely protoplasmic auxiliary cells in the 
floor of the fruiting body, and indirectly, by transmission from 
the pericarp through the sterile filaments. 
17. Grinnellia americana conforms in every phase of de- 
velopment to Schmitz’s law of apical growth. This law is 
exemplified in the germination of the spores, the growth of 
the fronds, the origin and development of antheridia and 
cystocarps, and the final separation of antherozoids and 
carpospores. 
State University of North Dakota, 
Grand Forks, North Dakota. 
References to Literature, 
Collins, F. S. In Notes on New England Algae, III, Bull. Torr. Bot. Club II 2 
29, 30, Mr. 1884. Records a striking exception to the rule, the presence 
of characteristic south shore New England Algae north of Cape Cod in 
Weymouth River and an adjoining cove. 
Farlow, W. G. The Marine Algae of New England. U. S. Fish Com. Report, 
1879, pp. 161, 162. 
Harvey, W. H. Ner. Am. Bor., Part II. 
Potter, M. C. Jour. Marine Biolog. Ass., pp. 171, 172. 1889. 
