418 
The sporangiferous joints have 6 peri- 
central cells, 4 of which cover the sporangium. 
As shown by FALKENBERG (1. c. p. 128, pl. 21 
fig. 9), a small peripheral cell situated to the 
right of the trichoblast of the foregoing joint 
is usually to be found (fig. 362); it is, how- 
ever, not always present (fig. 360). When 
going from one trichoblast to the next two 
pericentral cells are passed. 
The sporelings grow out to a vigorous 
straight primary shoot with early developed 
cortication, much bigger than the lateral 
branches. 
J. AGARDH distinguishes two main forms 
of the species: I. Lyngbyei and II. Ruchingeri, 
the first thinner, with flagelliform filaments 
and the upper branches tapering upwards from 
RE: a broader base, the latter thicker and more 
Polysiphonia one male plant, show- fleshy, with straight branches and the upper 
ing trichoblasts with two or three antheridial bodies ones attenuated upwards and downwards. 
and a cushion POS the OS Image! is said to be most frequent at 
the coasts of Sweden and Denmark (“in 
sinu Codano”), while the other occurs on the shores of the Atlantic Ocean. The 
characters mentioned seem, however, to be inappropriate as distinctive characters; thus 
in most specimens from the Danish waters not referable 
to f. baltica, branches attenuated towards the base may be 
found. Nor has Kyrın considered this character as con- 
clusive, having described under the f. Lyngbyei a new subf. 
gelatinosa with the branches attenuated downwards. 
This character is most prominent in the specimens from 
the North Sea, the Skagerak and the Northern Kattegat. 
Most of the specimens found in the Danish waters 
have been referred to f. {ypica though they are somewhat 
variable according to the localities. When growing in 
slight depth and exposed to light they become brevi- 
articulate, the joints in the upper part of the plant having 
only half the length or the same length as the breadth, Fig. 359. 
Q 0 Polysiphonia elongata. Ripe eystocarp. 
and the main axes become at least 1 mm thick. In onen 
greater depths the joints become longer. The typical form 
is common in the Danish waters from the North Sea to the western Baltic Sea, 
descending to 19 meters’ depth. The innermost places where it has been met with 
near low water mark are Svendborg (Sf), Kerteminde (Sb) and Hellebæk (Su). In 
