80 SPERMATOGENESIS AND FECUNDATION OF ZAMIA. 
as settling the matter for plants also, where the whole centrosome 
question is on an entirely different plane. 
In connection with Strasburger’s theory that the blepharoplasts of 
plants are derived from the cilia-forming organs of asexual swarm- 
spores, it is interesting to note that in ordinary ciliated animal cells a 
small, refractive, highly stainable body is developed at the base of each 
cilium with which it is connected—the so-called ‘‘ basal knob” which 
lies near the periphery of the cell. These bodies have recently been 
considered by Henneguy (53) and Lenhossek (78) as of the same nature 
as the centrosome. A recent contribution to this question by Stud- 
nicka (113) is of special interest in this connection. He has studied 
the position and relation of this body to the cilia in numerous inverte- 
brates and vertebrates in different ciliated cells, and concludes that 
this body (*‘/ussstiiche” or ** Blepharoplast”) can not be surely identi- 
fied with a centrosome. It is of special interest that in very many 
instances he found centrosomes near the blepharoplasts in the same 
cell (in Salamandra maculata and Petromyzon fluviatilis). It logically 
follows from this, as he states, that it ‘‘is hardly justified to always 
see in blepharoplasts specialized centrosomes.” It would follow from 
this, if the basal knob can be considered a blepharoplast, that they can 
exist independently in a cell near the centrosomes, from which it fol- 
lows that they can also appear in cells where no centrosomes exist. 
In tracing the derivation of the blepharoplasts it may be argued that 
while the centrosome is not at present developed normally in the 
various tissues of the Cycads, Ginkgo, etc., at one time they were 
formed normally in the various tissues, and in the course of phylo- 
genetic development have been gradually eliminated from the plant 
in general, being preserved and specialized only in the case of the 
spermatogenous cells where they serve an important and special func- 
tion. No evidence has as yet been brought forward, however, on 
which such a conclusion can be based. Strasburger’s recent researches 
(112) are of the greatest importance in pointing out the possible deriva- 
tion of the blepharoplast from organs other than centrosomes. He 
takes the view that the blepharoplasts of Zamza, Ginkgo, etc., are 
homologous to the cilia-forming organs of swarmspores in lower plants, 
and have been derived from them. In the formation of the swarm- 
spores in Vaucheria, Gdogonium, Cladophora, etc., Strasburger has 
found that the nuclei approach the plasma membrane of the cell, toward 
which it. becomes somewhat stretched out in the form of a beak. At 
the point where the nuclear beak or extension touches or approaches 
the plasma membrane a lens-shaped thickening of the membrane occurs 
from which the cilia are developed, a small knob being discernible at 
the base of each cilium. It has been thought that each of these knobs 
might represent a centrosome, but if so, they would be numerous and 
difficult to account for. No connection has been traced either between 
