608 Annals of the South African Museum. 



sperms inside the parent colony, no evidence in the African material 

 has been found to support them. Probably this is a case where 

 prolonged and careful observations of suitable living material will 

 reveal the true story. 



So far, then, this investigation adds nothing to our knowledge of 

 the process of fertilisation. The present position may be summed 

 up as follows : 



1. In F. Rousseletii in general the male globoids are produced in 

 great numbers in separate colonies from the eggs, very occasionally 

 one or two appearing in preponderatingly female colonies. In 

 V. capensis a comparatively small number of male globoids (5 to 22) 

 are produced in the same colony as the oospheres ; always where the 

 colonies are monoecious they are strongly protandrous. 



2. In both species male globoids are liberated outwards, and 

 eventually dissociate in the water ; more rarely liberation takes 

 place inwards, and dissociation follows within the body of the parent 

 colony. 



3. The apex of the flask-shaped oosphere remains near the surface 

 of the parent colony, and has the appearance of a receptive spot. 



4. Later, presumably after fertilisation, the neck of the oosphere 

 is withdrawn, the oospore rounds off, clothes itself with a several- 

 layered wall, and is deep sunk within the parent. 



5. Sperms are frequently found in both species within the colony, 

 apparently swarming round young oospheres and endeavouring to 

 penetrate the surrounding vesicle. 



6. No posterior pore can be detected in the parent colony after 

 the closure of the phialopore. 



From these facts the following deductions can be made : 



(a) If fertilisation takes place it must in general be cross fertilisa- 

 tion, since ripe oospheres and mature sperm bundles are very rarely 

 met with in one and the same colony even if monoecious. 



(6) Judging from the behaviour of the oospheres, fertilisation from 

 without via the neck of the oosphere would seem probable, but at 

 present there is no further evidence of such being the case, while 

 the frequent presence of sperms within the colony indicates that 

 by some means the sperms penetrate into the hollow of the parent 

 colony, and may thence enter the oosphere by the broad basal 

 part. 



Overton, by means of isolation experiments (1889, p. 245), demon- 

 strated that in V. globator self-fertilisation could take place, and he 

 held that self-fertilisation was usual, a conclusion with which Klein 



