191S] Gardner: New Pacific Coast Manne Algae III 457 



scraped from tlie filaments and magnified revealed a surprising varia- 

 tion in the shape and size of the vegetative cells, as well as of the 

 gonidangia. Among the collection one could select cells in both vege- 

 tative and reproductive conditions which would conform to the descrip- 

 tion, in shape and in size, of each of several well-known species, but 

 since there is such perfect gradation in lengths and in widths, both in 

 the purely vegetative cells and in the gonidangia, ranging in size of 

 mature cells from 6fx to 40/a wide in the upper parts, and from 40ju. to 

 VZO/x long, it is impossible to segregate them into species. Considered 

 as a species, D. protea represents the largest known species of Dcnno- 

 carpa, and has the greatest range of variation in size and in shape of 

 the cells. Plate 38, fig. 4, represents some of these found among the 

 gonidangia. 



Dcrmocarpa protea is an excellent example of the formation of 

 gonidia by successive and progi'essive divisions of the gonidangia to 

 form gonidia (pi. 38, fig. 5). This method is represented in the 

 gonidangia irrespective of shapes and sizes, and is another evidence 

 in support of their all belonging to a single species. 



Kirchner (1898, p. 58), in his key to the genera, places Dcrmocarpa 

 in the group which produces the gonidia by simultaneous division of 

 the protoplast. In my Cytological Studies in Cyanophyceae (1906, 

 p. 281), I expressed the opinion that Dcrmocarpa fucicola Saunders 

 produces gonidia in this manner. I have since examined authentic 

 material of that species and, although the gonidangia are very sparse, 

 it appears to form them by simultaneous division, but having examined 

 other collections from our coast which seem to be of the same species, 

 judging from the shape and size of the cells, which clearly show that 

 the formation of gonidia is by successive divisions of the protoplast, 

 some doubt may still be entertained as to which method D. fucicola 

 follows. This subject must have more careful study and may prove 

 to be a more stable character than shapes and sizes of cells upon wliich 

 to establish species. 



Dermocarpa sphaerica Setchell et Gardner sp. nov. 

 Plate 39, fig. 14 



Cellulis solitariis aut coutiguis, sphaericis, 8-16/t diam., dilute 

 coeruleo-viridibus ; parietibus tenuibus, hyalinis; cytio]ilasmate minute 

 granulato; gonidangiis sphaericis 8-1 6/i diam.; gonidiis primo angu- 

 latis demum maturitate sphaericis 2-5. 3/a diam., divisionibus simul- 

 taneis formatis, dissolutione parietis gonidangii totii liberatis. 



