Notes . 
949 
occurs at both ends. In Fig. 7 a pollen-sacs have completely developed and dehiscence 
has taken place, leaving disorganized cells and a few pollen-grains within the fibrous 
Figs, i a, 3 a, 7 a, and 8 a. 
layer. It may be added that the flowers showed a further deviation from the normal 
in having the top of the ovary and the styles glabrous. 
J. J. CLARK. 
Royal Botanic Gardens, 
Kew. 
ON WELL-MARKED AEROTROPIC GROWTHS OF BACILLUS ME- 
GATHERIUM. — For nearly three years I have had under my observation aerotropic 
growths of Bacillus megatherium which present a remarkable annual periodicity. 
These growths were first noticed on the removal of some boards forming the front of 
a large box in which the palm Demonorops was growing. On the projecting dead 
extremities of the roots and the surrounding earth thus exposed, white fungal masses 
