1919] Setchell-Gardncr : Myxophyceae 39 



quently entophysaloid colonies, 40-60/1, up to 200/i, diiim., by cell 

 divisions witliont rupturing the origiiuil tegument ; teguments firm, 

 slightly mucilagenous on the surface, j'ellowish brown, 2ix thick ; proto- 

 plast homogeneous, light blue-green ; gonidia formed in unchanged 

 vegetative cells of either the small or the large colonies, 3-3. 5ja diam. 



Growing on rocks in th(^ upper littoral belt. Carmel Bay, ]\Ion- 

 terey County, California. 



Setchell and Gardner, in Gardner, New Pac. Coast Alg. Ill, 1918a, 

 p. 463, pi. 41, fig. 30. Plrurocapsa fuUginosa Collins, Holden and 

 Setchell, Phyc. Bor.-Amer. (Exsicc), no. 704 (not of Hauck), 



Pleurocapsa entopJujsaloidcs is closely related to P. fulUjinuaa 

 Ilauck (1885, p. 515, fig. 231) but differs from it in having slightly 

 larger colonies which are often entophysaloid (pi. 7, fig. 30), in hav- 

 ing a blue-green protoplast, a yellowish brown tegument, in having 

 slightl}^ larger vegetative cells and in having gonidia develop in the 

 small vegetative cells. In this last statement concerning the size of 

 the cells, we are assuming that Hauck intended to include the large 

 spherical cells which he figures, and which would ordinarily be con- 

 sidered gonidangia, in his measurement "Zellen 5-20|U, dick." We 

 have examined a bit of the type material of his P. fuUginosa and find 

 that the vegetative cells of our species are slightly larger than the 

 cells which we consider to be the vegetative cells of the type. Hauck 

 does not mention gonidangia but he figures, in addition to groups of 

 two, four, to many cells, four large spherical cells, one of which is 

 filled witli undoubted gonidia. The presence of these two forms 

 and sizes of cells brings up the question as to whether or not we are 

 dealing with a single species or with two species, and if the latter, 

 the two species probably belong to different genera. We have been 

 puzzled with several similar mixtures collected on our coast. We 

 are of the opinion that we have to reckon with two species in tliese 

 eases and in the case of P. fuUginosa. Now that we have discovered 

 gonidia in these colonies of small vegetative cells in at least two species 

 of Pleurocapsa, viz., P. cntophysaloidcs and P. gloeocapsoides, the 

 evidence in favor of considering that such mixtures as mentioned 

 above belong to two species is stronger. Either we may take this view 

 of the matter or we may note that we have two lines of development 

 in a single species. One starts with a single cell, e.g., a gonidium, 

 and, after enlarging to mature size, divides in three planes succes- 

 sively, more or less at right angles to each other, the process continuing 

 until a smaller or larger colonj^ is built up, according to the species, 



