TAXONOMY 
247 
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 C 0 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 cases of parasites, the absorbing connections which are more or 
less specialized and definite are called haustoria. In the higher forms 
the hyphae become consolidated into false tissues, and assume definite 
shapes according to the species. Of this character are the fructi¬ 
fying organs which constitute the above ground parts of Puff Balls, 
Cup Fungi, Mushrooms, etc. There are four classes of Fungi, viz.: 
Phycomycetes, Ascomycetes, Basidiomycetes and Fungi Imperfecti. 
Class I.— Phycomycetes, or Alga-like Fungi 
The Phycomycetes represent a small group of fungi showing close 
affinity with the green algae. Their mycelium is composed of coeno- 
cytic hyphae, which suggests a close relation with the Siphonales 
group of green algae. Their sexual organs are likewise similar in 
structure. Transverse septa appear upon the formation of repro¬ 
ductive organs separating these structures from the vegetative 
hyphae. 
