504 



S. O. MAST 



Chlamydomonas {fiuvialis and globulosa)? 



Various species of Chalmydomonas were found in abundance 

 at different times in the pools about the laboratory at Nela 

 Park, but during the time the following tests were made they 

 were not very abundant and orientation was rather indefinite, so 

 that it was not possible to obtain very accurate results. 



Two species were present in the culture studied. One was 

 ellipsoidal in form with a maximum diameter of only about 6 n, 

 the other was nearly spherical and very much larger, having a 

 diameter of approximately 30 fx. The former was probably C. 

 fluviahs and the latter C. globulosa. 



Most of the observations were made on the larger species, but 

 both were continuously present in the test aquarium and the 

 reactions in both appeared to be the same. 



TABLE 8 

 Chlamydomonas sp? (positive). Relation between wave-length and stimulation 



For description of table see legend table 2, page 492. 



From August 8 to 11 inclusive some specimens brought directly 

 from the pools and others taken from solutions brought from the 

 pools and kept in the laboratory were repeatedly tested in the 

 spectrum under various conditions of illumination. They were 

 found to be positive most of the time but orientation was usually 

 so indefinite that only a few entire series of readings were 

 obtained. 



