394 THE ZOOLOGIST. 
pendently, like any free aquatic animal, to the distant female 
organ, there to complete fertilisation. In the case of phanerogams 
the independent mobility of the pollen-grains is an impossibility. 
To effect the union of pollen-grains with that particular part of 
the female flower which is destined to receive them, some external 
agent must interfere. In many cases, especially in the lower 
orders of the floral world, the wind, gravitation, or both together, 
are the agents in question; in the majority of higher phanerogams, 
insects, or occasionally other animals, are instrumental in con- 
veying the pollen. 
Now there are a great number of cryptogams in which the 
male sexual cells which are emptied into the water do not possess 
the faculty of independent motion, as they are not endowed with 
cilia, and are therefore dependent on the action of external forces 
for their locomotion. To these belong the great and highly 
differentiated order of so-called “red sea-weeds,” or Floridee, 
chiefly marine plants which in form and colour develop a number 
of wonderfully beautiful varieties, which no one who has ever 
attentively observed them on the sea coast will ever forget. 
Their antherozoids, which are generally spherical, are dis- 
charged into the water as motionless cells, and are yielded up to 
the play of currents, in the same way as, in the anemophilous 
phanerogams, the pollen-grains pass as a dust into the atmosphere 
from the anthers, and are moved to and fro by the wind. There 
are many analogies between Floride@ and higher phanerogams 
as regards their sexual conditions. Thus amongst the former we 
find many species which are diccious, similar to the lowest 
phanerogams amongst gymnosperms, and to others of higher 
order. The chances of fertilisation in their case are, therefore, 
similar to those applying to diccious phanerogams. Often 
the male plants grow at a considerable distance from the female 
plants of the same species. In the spring of 1878 Dr. Dodel- 
Port, during a series of microscopical examinations of Adriatic 
red sea-weeds extending over four weeks, found only female and 
agamic (tetrasporous) specimens of Polysiphonia subulata, and 
looked in vain for male specimens, of which only at the end 
of his investigations he could obtain a few. Their respective 
localities of growth were evidently considerably apart, and yet at 
all times Dr. Dodel-Port found female. specimens in all stages 
of fertilisation. ‘lhe antherozoids ejected by the male plants 
