Notes . 
417 
another (also undetermined) species from a tank in one of the pits at 
Kew. I was able to determine this point by the number of caps 
found on the apical cell of few-celled individuals ; these were always 
found to be one less than the number of cells present. If the first 
cap had been cast off, their number must have been two less. 
Probably the case observed by Poulsen is not very common in 
Oedogomutn, or rather, although for all I can say, the formation of 
the first ring may always take place in the above-described peculiar 
manner, the cap is certainly very often retained. 
Jodrell Laboratory, Kew. 
F. E. FRITSCH. 
