Inter-Relationships of Protista and Primitive Fungi. 103 
confusion in the literature, are marked by the development of (1) a 
chitinous cup or theca within which the organism lives and (2) a 
protoplasmic collar-like outgrowth of the anterior end of the body. 
The first of these lines begins with Codonceca (Fig. 2, B), in which 
the organism is sessile in the cup, and probably leads through 
Dicceca (Fig. 2, C, D) in which there is a stalk, to the dendroid 
colonial genus Poteriodendron (Fig. 2, E). In these three genera 
the lip-like anterior projection foreshadowed in Oikornonas becomes 
more pronounced and the line marked by the possession of a well- 
developed plasmatic collar or peristome which is a modification of 
the ectoplasm of the anterior end of the body and which divides 
along with the latter, the plane of division being longitudinal as is 
usual in Flagellata though sometimes transverse ; Codonosiga shows 
both longitudinal division involving the peristome (Fig. 2, F) and 
transverse division which occurs below the peristome, the lower 
half after division producing a new peristome of its own (Fig. 2, G). 
By the cohesion of the products of division in Codonosiga-Whe. 
types there arise colonial forms such as Codonocladium (Fig. 2, H); 
while a further line begins with Salpingoeca (Fig. 2, I), combining 
the characters of Codonceca and Codosiga and having both theca 
and peristome, and leaning also to colonial forms, such as Polyceca 
(Fig. 2, J). A further choanoflagellate line begins with Diplosiga 
(Fig. 2, K) in which there are two concentric collars, and this line 
also leads to colonial forms. 
The second main group of Protomastiginese is biflagellate and 
isomastigote, being characterised by two flagella of equal length and 
both directed forwards. The simplest form, AmpJiimonas (Fig. 2, L), 
is practically a biflagellate Oilzomonas , while Diplomita (Fig. 2, M) 
has a theca and corresponds to a biflagellate Codonceca or Dicceca ; 
from both there arise branching colonial forms. In these forms 
(Amphimonadaceas) as in Oikomonas, etc., food is ingested by an 
anterior vacuole. 
In the remaining Protomastigineas with 2 or more flagella 
there is usually a marked difference in length or function or both 
between the flagella, often accompanied by specialisation of the cell 
in other respects. In the Monadaceae (Paramastigoda) there is 
one long flagellum and one (rarely two) short accessory flagellum 
near its base; here also vacuolar ingestion takes place at the 
anterior end of the body. The Monadaceae may be derived from 
the Amphimonads, or perhaps independently from a biflagellate 
Pantostomatinean like Cercobodo. In some species of Monas 
(Fig. 2, N) there are two short flagella; Physomonas (Fig. 2, O) 
shows a remarkable resemblance to Actinomonas, having numerous 
radiating thread-like pseudopodia; and there are branched colonial 
forms corresponding to those found in the uniflagellate families 
( Dendromonas , Anthophysa, etc.). Some of the simple Monadaceae 
{Monas spp.) have an eye-spot and produce leucosin instead of the 
oil which is the characteristic product of the Flagellata, and in 
these respects as well as in the resemblance in general structure 
(apart from absence of chromatophores) and in mode of cyst 
formation they so closely approach the Ochromonads among the 
Chrysomonadineae (see Cavers, 1913) that they may well be regarded 
as colourless forms derived from these brown Flagellates. Moreover, 
among the Chloromonads there are forms which strongly resemble 
