108 Cc. CLIFFORD DOBELL. 
This led to the formulation of the well-known Lenhossék- 
Henneguy hypothesis, which states that the centrosomes 
form the basal granules of flagella and cilia. The work of 
Gurwitsch, Maier, Henry and others on ciliated epithelium 
and infusoria clearly shows that this generalisation cannot 
be made. The flagella certainly arise from centrosomes in 
sperms and in the so-called “ Centralgeissel ” arrangement, 
but not as a rule in other cases. The basal granules of 
flagella and cilia appear to be merely cytoplasmic thickenings 
in most cases (Henry, Gurwitsch, etc.). 
The possible homology of the basal granule with the 
trypanosome blepharoplast! must not be forgotten. For a 
long time the nature of this structure remained doubtful. 
Wasielewsky and Senn regarded it as an ectoplasmic thick- 
ening, a kinoplasmic differentiation unrelated to the nucleus. 
Rabinowitsch and Kempner thought it was a nucleolus. And 
whilst Laveran and Mesnil regarded it, from a Lenhossék- 
Henneguy point of view, as a centrosome, Bradford and 
Plimmer compared it with the infusorian micronucleus. Its 
real nature was revealed by Schaudinn’s study of Haemo- 
proteus noctue (43). He showed that it was a separate 
nucleus specially concerned with the locomotory functions of 
the cell, a kinetonucleus, taking origin from the original 
compound nucleus. ‘The origin of the blepharoplast from the 
synkaryon has since been observed by Bradford and Plimmer 
in Trypanosoma brucii. 
From the kinetonucleus the flagellum takes origin. It is, 
however, a true nucleus, undergoing reduction and fusion at 
conjugation. A similar reduction, etc., occurs in Herpeto- 
monas, according to Prowazek (38). 
My observations on the basal granule of Copromonas and 
the part it plays in division (see p. 90) suggest that it may 
indeed be homologous with the kinetonucleus. An interesting 
comparison may be made with the flagellar apparatus in 
some Rhizomastigina. In Mastigamceba Prowazek (86) 
states that the flagellum is retracted into the nucleus before 
1 For the more important literature see Woodcock (54). 
