130 SEXES ? OF FUCUS, [BOOK i. 



slight lateral depressions indicating its future division into 

 two sporules. The whole contour of the epispore presents a 

 large quantity of very delicate folds which disappear soon 

 after the spore has fallen to the bottom of the water ; the 

 epispore then rapidly distends and forms round each sporule 

 a large transparent limb covered all over with cilia?. 



" The conceptacles of Fucus tuberculatus are, as it were, 

 divided into two parts ; the upper half near the ostiole is 

 covered with antheridia ; the other half at the bottom of the 

 conceptacle is reserved for the spores. We may compare 

 this arrangement to the inflorescence of the fig. The spores 

 seem to remain undivided and not to become broken up into 

 sporules as in the other Fuci. However, we must add, that 

 the specimens which we had the opportunity of examining 

 were not sufficiently fresh to enable us to be certain on this 

 point. 



" The antheridia of this Algal are not, like those of the pre- 

 ceding species, formed of a double envelope; the interior 

 vesicle is wanting, and that which we have compared to a 

 perispore is alone to be found. The corpuscles expelled 

 directly from the latter, remain for some time collected 

 together, in a bunch, before they disperse in the water. We 

 have observed the same thing in another Algal with herma- 

 phrodite conceptacles (Halidrys siliquosa) the spores of which 

 also appear to remain entire. The corpuscles are shaped 

 rather differently from the others, and the arrangement of 

 the cilise is precisely the inverse of that formerly described. 

 The corpuscle, when in motion, turns upon itself, the longest 

 cilia, which is agitated with great rapidity, being foremost, 

 whilst the short one, inserted in the red granule, remains 

 still. 



"From what we have now said, it cannot, we think, be 

 doubted that Fuci have a sexual apparatus analogous to that 

 granted to exist in Charas, Mosses and Liverworts, a sexuality 

 which is, it is true, as yet doubtful, and of which we have no 

 other proof than the observations of MM. Bruch and 

 Schimper on Encalypta streptocarpa." (Bryologia Europaa, 

 fascic. iv.) 



Finally, Mr. Thwaites is inclined to recognise a sexual element 



