TAXONOMY 
195 
Chondrus, Irish Moss or Carragheen. Both are purplish-red in 
color. Each consists of a dichotomously branched thallus the 
lower portion of which is differentiated as a stipe or stalk; the basal 
portion of which, called the holdfast, clings to the rock. The upper 
part is several times forked and its terminal segments appear notched 
or bilobed. Scattered here and there over the segments of the thallus 
will be noted sporangia which, when mature, contain tetraspores. 
In Chondrus crispus the sporangia are elliptical and embedded in 
the thallus near its surface, whereas in Gigartina they are ovate and 
project outward from the surface of the segments. Upon the ripen- 
I ing of these structures the spores are discharged into the sea water. 
These sooner or later germinate into new Chondrus or Gigartina 
organisms. The dried mucilaginous substance extracted from 
Gracilaria lichenoides, Gelidium and Gloiopeltis and other species of 
red algae growing in the sea along the eastern coast of Asia con- 
stitutes the drug Agar, a most valuable ingredient in culture media 
[ as well as a laxative. 
Rhodymenia palmata or Irish Dulse is a purplish-red, flat, mem- 
branous, palmately cleft or dichotomous red alga growing on the 
tissues of other algae along northern shores of the Atlantic between 
the low- and high-tide marks. 
SUBDIVISION IV.— FUNGI 
This great assemblage of thallophytes is characterized by the total 
absence of chlorophyll and so its members possess no independent 
power of manufacturing food materials such as starches, sugars, etc., 
from C0 2 and H 2 0. Consequently they are either parasites , depend- 
ing for their nourishment upon other living plants or animals, called 
hosts; or saprophytes, depending upon decaying animal or vegetable 
matter in solution. Some forms are able to live either as saprophytes 
or parasites while others are restricted to either the parasitic or 
saprophytic habit. The vegetative body of a fungus is known as a 
mycelium. It consists of interlacing and branching filaments 
called hyphce, which ramify through decaying matter or invade the 
tissues of living organisms and derive nourishment therefrom. In 
the case of parasites, the absorbing connections which are more or less 
