368 BOTAMCAL GAZETTE [November 



medium is the case of castor-oil soap, a o. i per cent concentration 

 of which is an almost solid jelly (21). 

 * Thus is it seen that in giving viscosity values it is necessary 

 to distinguish between protoplasm as a whole and its constituent 

 parts, especially the matrix (hyaloplasm). I prefer to use the term 

 matrix rather than hyaloplasm, owing to the confusion which 

 exists in the use of the latter word. Hyaloplasm, as first used by 

 Hanstein (ii), designated "the homogeneous ground substance'' 

 of protoplasm as distinguished from the granules suspended in it. 

 Homogeneity of the ground substance, however, is not definitely 

 established. Chambers (6) and Wilson (27) have employed hyalo- 

 plasm to mean the " interalveolar substance." Wilson (29), 

 however, admits the possibility of using the word in the exactly 

 opposite connotation; that is, the ground substance (also termed 

 cell sap, enchylema, hyaloplasm, etc.) is the "alveolar substance 1 ' 

 which fills the alveoli. If we accept Butschli's (4) contention 

 that the hyaloplasm (the peripheral granular-free border) of 

 Myxomycetes is not homogeneous, but is of a definite alveolar 

 structure, then this hyaloplasm must be regarded as including 

 both phases of the emulsoid structure; that is, as consisting of 

 interalveolar and intraalveolar substance. 



Material 



The data upon which the following discussions are based were 

 obtained by a study of a considerable variety of material. Conse- 

 quently, the conclusions reached may be regarded as rather gener- 

 ally applicable. Since prominent dissimilarities do occur in the 

 properties of widely differing and sometimes of closely related 

 genera, however, it is to be understood that the statements made 

 refer only to the organism under discussion at the time, although 

 many of the general deductions apply to the protoplasm of all the 

 organisms worked upon, if indeed they are not applicable to all 

 living substance. 



The following types are the chief ones which were used for this 

 study: the Myxomycetes Ceratiomyxa, Badhamia, Arcyria, Cri- 

 braria, and Fuligo; the rockweed Fucus; the fresh water algae 

 Spirogym and Vaucheria; the bread molds Rhizopus and Zygo- 

 rhynchus; pollen tubes of the blue-flag Iris versicolor, of the beach- 











