517 
layers are, however, not regularly concentrical, the separate layers not usually 
continuing round the stem, for which reason the number of layers may be much 
greater on one side than on the other. The 
boundary of a layer may meet that of the fore- 
going layer or it may gradually disappear 
(fig. 485). 
The antheridia are produced in particular 
yellowish or nearly colourless folioles borne on 
the border of the upper part of the flat fronds 
of the male plants. The androphores are up 
to 2 mm long, totally covered with spermatia- 
producing cells, sometimes with the exception of 
the outmost tip that remains sterile. The antheridia 
were first described by BurrHam (1891), later 
by DARBISHIRE (1895, p.30) who showed that 
the spermatia are produced in conceptacles that 
are provided with an orifice in the roof. Kyrın 
(1928, p. 54) did not observe these orifices, but 
Fig. 485. 
Phyllophora membranifolia. Transverse section 
of stem near the base. 86: 1. 
I can confirm their existence; they arise by dissolution of a distinct area of the 
on the margin of the flat frond 
at a considerable distance from 
Fig. 486. 
Phyllophora mem- 
branifolia. Male the cylindrical base. The carpo- 
plant with andro- 
phores. Nat. size, Pores arise in July. The carpo- 
gonial branch is three-celled 
(comp. SCHMITZ u. HAUPTFLEISCH p. 253, KYLIN 
1928, p. 55, K. RosENVINGE 1929, p. 12"). Fig. 
491 shows carpogonial branches isolated by 
outer wall. I found the conceptacles close together, not separated by 
sterile cells (fig. 487). The spermatia are about 6 w long, 3 w broad. 
Antheridia were observed from June to October. 
The procarps arise in considerable number in particular oblong 
or nearly globular short-stalked carpophores borne on the upper part of 
the cylindrical and the lower part of the flat thallus of the female 
plants (fig. 488). In the latter case the carpophores are mostly placed 
on the border but often on the flat side too. In a short-stemmed 
specimen from the North-Sea (fig. 490) the carpophores were borne 
pressure and separated from the supporting cell Fig. 487. 
which later functions as auxiliary cell. The Phyllophora membranifolia. Transverse section of 
ins 3 4 androphore showing fourantheridial crypts. 625 : 1. 
carposonium gives off downwards a prolonga- 
fo) Oo Oo 
tion that is connected with the second cell of the carpogonial branch through a lateral 
! According to DARBISHIRE 1895, p. 31 the carpogonial branch is four-celled; the first cell, how- 
ever, does not belong to the carpogonial branch but is the supporting cell, the later auxiliary cell. 
