10 NERVOUS SYSTEM AND SENSE ORGANS 
of the body. The basal granules of cilia, cirri, and membranelles 
are considered as secondary rather than primary structures. In 
ciliates the connection between neuromotor apparatus and cilia is 
not clearly established, but there is some indication that there may 
be connection. 
In many flagellate protozoans the flagellum has been described 
as springing from a center or blepharoplast. A very primitive type 
of neuromotor apparatus is described by Wilson, 1916. The flagel- 
lum arises from a blepharoplast which grows out from the central 
karyosome (Fig. 2, A-D). The blepharoplast is connected with 
the karyosome by a rhizoplast. 
In other forms the blepharoplast may be composed of one or 
more granules which may or may not be connected with the nucleus. 
The basal granule of the flagellum may have a double function of 
being a basal granule of the flagellum and also a division center for 
the cell. In some forms the two functions are separated in two 
granules. In some a number of granules surround the blepharo- 
plast or may be derived from it. These migrate backwards. and 
come to form the parabasal body which may in some cases be at- 
tached by a number of fibrils to the blepharoplast. This parabasal 
body is interpreted as an accessory kinetic reservoir. A further 
elaboration of this structure is the chromatic rod of some species. 
Various types of flagellates with their internal connections are 
shown in Fig. 3. One of the most complex conditions we find in 
Giardia, Kofoid and Christianson, 1915. This is a binucleate organ- 
ism equivalent to two flagellates, each containing one nucleus and 
one blepharoplast at the end of a single axostyle, three flagella and 
a half or whole axostyle, depending upon the stage of the organism. 
Two blepharoplasts are connected by cross commissures and are 
anterior. The lateral flagella cross the middle line. The blepharo- 
plasts are joined to the nuclei by rhizoplasts and also to the para- 
basal body lying along the axostyle. Each organism has its own 
neuromotor apparatus, but due to the crossing of the fibers between 
the blepharoplasts the two organisms are unified. (Fig. 2, M.) 
According to Yocum and others the motorium of ciliates is 
homologous with the blepharoplast of flagellates. According to 
Dobell the blepharoplast of the protozoan is homologous with the 
end knob and the axial filament of the metazoan sperm, whose func- 
tion is to provide for the locomotoror activities of the cell. These 
structures are also homologous with the centrosome of resting cells. 
It seems probable that other strands and coérdinating centers 
may be found in protzoans in addition to those already described. 
This type of system for control or codrdination is not in any sense 
homologous with that of Metozoa and in no sense does it lead to 
development of the nervous system of more complex forms. From 
what has already been said it is probable that methods of codrdina- 
tion are not at all alike in Protozoa and Metazoa; in fact it may well 
