8 Dr. G. Dickie on the Marine Algee 



In the sacs containing simple filaments and at their bases, we 

 find the seeds properly so called. These Montagne calls basi- 

 sperms, from their position in relation to the filaments, and in 

 order to distinguish them from the other kind of fructification. 

 The seeds are usually imbedded in a gelatinous secretion. In 

 some concejjtaclesvie find ir«ncAe^ filaments which are also jointed, 

 and in the upper articulations of which we observe the other 

 kind of reproductive bodies called acrosperms by Montagne, the 

 microphytes of De la Pylaie, alluded to also by Meneghini, and 

 figured by Lyngbye (Montagne, loc. cit.). It must not be sup- 

 posed, however, that the acrosperms are invariably contained in 

 the terminal joints of the filaments ; the term is, however, sufficient 

 to express the general difference in position of the two kinds of 

 bodies, in relation to the filaments. 



On the sm'face of the frond in many of the Fucoidece are nu- 

 merous pores, from which issue, as Greville remarks, " little tufts 

 of filaments, the use of which has not been discovered." These 

 I believe to be barren conceptacles ; both the barren and fertile 

 are in reality mere inflexions of the surface of the frond. The 

 natm'e of the fructification in Asperococcus appears to be in fa- 

 vour of this opinion ; in the A. fistulosus we have in reality the 

 basisperms and simple filaments of a Fucus completely exposed, 

 there being no inflexion of the surface. 



Tm-ner states that Reaumur considered the tufts of fibres 

 arising from the pores on the frond as corresponding to the 

 anthers of Phsenogamous plants. 



Fucus vesiculosus. — This species is abundant, and particularly 

 near high-water mark and at estuaries. Dr. Montagne has only 

 found basisperms in three specimens which he examined. It how- 

 ever possesses also acrosperms, the two kinds occurring on differ- 

 ent plants. 



F. ceranoides. — In this vicinity it is only found at the mouths 

 of the Dee and Don, and also some distance up these rivers. It 

 in some instances makes a close approach to F. vesiculosus, and 

 is probably only a variety of it, produced by the action of fresh 

 or brackish water. Like the former species also, it possesses both 

 kinds of reproductive bodies, which are found on the same plant, 

 but on different fronds. 



F. nodosus. — This species is found in great profusion. Mon- 

 tagne and Pylaie have only found on it acrosperms, Lyngbye de- 

 tected basisperms; Turner says that both occm* in the same con- 

 ceptacles. I have found both, but on different plants, and have 

 been unable to confirm Turner's observations. 



F. serratus. — Abundant. This species possesses both kinds of 

 reproductive bodies on the same plant, but on different fronds. 



F. caiialicuJafus is very common ; for the most part an occa- 



