90 



Figure 2. 



Opposite direction. A case of this kind is also shown l)y A. Tri'indh^' and in 

 the above mentioned form. 



In some otlier cases, as has been lonnd liefore. three lilanients of 

 Spirosyra crassa eonjns^ate with one anotlier- withont regularity, as is seen 

 in Fig. 3. Part of tlie time the contents of the cells move from the tila- 

 raents A to B, in some cases from P. to A and in others from P> to ('. 



Figure 3. 



In another instance in this material three tilaments of Spirosjyra 

 cras.sa were found connected by ((injii^iatini,' tubes.' In I'ii;. 4 the cells of i 

 the two outer filaments A and C \\('ie in some casi-s conjuiiatius with the 

 cells of the lilamcnt It, and tiius I'nrniiim a sinu'lc Zyi^'ospoi-c frniii tjie con- 



' ,\ Trondlc — IJbiT die Kopulnlion niiii Kiiiiiuiii; von Spirciuyra IJndmisflu 

 ZeitiniK, 1907. Vol. 65, p. 192. 

 - \. Trondlc 1. c. 

 •■' Bcnuoti; and Murray, Cryptoganiic Uuiaii.v. p. I'(i7. 



