9 2 Church . — The Polymorphy of 
Kuckuck’s plants came up spontaneously in the tanks of 
the Heligoland Laboratory in the summer of 1893, and grew 
as short filaments attached to stones which had been collected 
in the North Haven in fairly shallow water (1-3 fathoms). 
Similar plants were found in reproduction in July, forming 
brown Elachista- like tufts on Plocamium , and sterile plants 
also as late as December. 
Normal Cutler ia is said to have been gathered at Heligoland 
by Wollny, but has not been known to occur there since ; 
and although Kuckuck appears to infer that his plants 
reproduced their like, it is quite probable that they had 
all sprung from Aglaozonia-spores, and owed their late and 
feeble development to the cold spring and early summer 
of the North Sea; and that thus unfavourable conditions 
had led to a vegetative degeneration similar to that observed 
in the Plymouth cultures. 
But if they had been reproduced from oospheres similar 
to those they bore, the confirmation of the development of 
a protonematoid embryo from a Cutleria- form would be 
of still greater theoretical interest, as confirming Thuret’s 
original observation, and thereby assisting in the demolition 
of the theory of inherent necessity of an alternation of growth- 
forms. 
Seasonal Dimorphism. 
From the preceding considerations it is obvious that the 
polymorphy of Cutleria presents little in common with the 
antithetic alternation of primitive gametophyte and nursed 
sporophyte of the Archegoniatae ; and still less with the 
case of Coleochaete and the Florideae, in which the origin 
of what in these forms is generally regarded as a sporophyte 
may be sought in polyembryony. 
From the homology of the Aglaozonia-thaMus with other 
asexual Algae such as Battersia or even Laminaria , Aglao- 
zonia has as much claim to be regarded as theoretically 
a gametophyte as any other Alga. It might even be urged, 
