
INTRODUCTION TO PLANT HISTOLOGY 48 
Vaucheria shows considerable 
differentiation: (1) It has’ 

enmreerreonrecmemnronee ns serra ot eer sea seen oon cosnzsseeseneanrermmemreremnsera 
: | Fic. 7,—VAUCHERIA. | 
p, protoplasm with chlorophyll; ¢c.w, cell-wall; sp, spore; 7, organ of 
attachment. 
an organ of attachment which 
answers in partto a root, although 
it has not the structure of the root 
ot higher plants. (2) The shoot 
is often much branched, some 
branches being modified into 
organs of reproduction or attach- 
ment, as in the rooting portion. 
Chlorophyll is present in oval 
or spindle-shaped bodies, sus- 
pended in the protoplasm. Vau- 
cheria, though not multicellular, 
IS an advance on Protococcus, 
for, owing to the greater dif- 
ferentiation, more division of 
labour is possible. | 
The fresh - water 
Alga, Spirogyra, may 
next be studied. It is found in 
Ponds, in company with many 
other Alge, which form the 
green, slimy growth on the sur- 
face of the water. If some of 
Spirogyra, 

Fic. 8.—SPIROGYRA. 
p, protoplasm with spiral 
bands of chlorophyll; x, nu- 
cleus with connecting threads 
of protoplasm; ¢.w, cell-wall. 
this green substance is placed on a glass slide, and the 
+ 
