CHLOROPHYCE^] 



149 



above each other (Fig. 44). Halicoryne is, in fact, a 

 better representative of the Acetabulariece than the 

 disc-forming Acetabularia, since it supplies us with a 

 link to the other Dasycladacew, from which it is distin- 

 guished, however, by the alternation of fertile and 



FIG. 44. Acetabularia crenulata with several caps in longitudinal section 

 highly magnified. (After Solms-Laubach.) 



sterile whorls, in addition to the more important 

 characters of the sporangia. The genus Chalmasia 

 (like the former genus Polyphysd) has no corona in- 

 ferior, and while closely resembling Acetabularia in 

 most respects, agrees completely with Halicoryne in 

 the structure of the spores. In Halicoryne their mem- 



