180 T. H. BUFFHAM ON BOtfNEMAISONIA HAMIFERA. 



(Yokosuka on the Admiralty charts) is on the south coast of 

 Nipon (Japan), Long 138° E., and Lat. 34° 41' N. Un- 

 doubtedly in this latitude the sea would be warmer than any 

 British waters. We do not know the limits within which B. 

 hamifera can exist. It is noteworthy, however, that the gather- 

 ing of Dr. Savatier, which comprised altogether only 54 species 

 and varieties, contained 21 species which had not previously 

 been recorded from Japan, and that these new records included 

 some of our common British species, such as Monostroma Lac- 

 tuca, Ulva Linza Harv., Chorda Filum, Chordaria divaricata, 

 Dictyota dichotoma, Padina Pavonia, Bictyopteris polypodioides, 

 Asperococcus bullosas, Laminaria flexicatdis, Chylocladia Jcali- 

 formis, Fastigiaria furcellata, Melobesia membranacea, M. cortici- 

 formis, Gracilaria compressa, Halurus eqnisetifolius. This would 

 rather indicate that, so far as temperature is concerned, the 

 Japanese station may differ not considerably from our southern- 

 most coasts. 



It is impossible that the Falmouth specimens can have been 

 brought from Japan, and it is certain that they grew near the 

 station where they were found, for they were quite fresh (and 

 anyone familiar with Bonnemaisonia will know how evanescent 

 is its fresh beauty), of rich colour, and the delicate procarps 

 with trichogynes were abundant and in perfect condition. 

 Nevertheless I am disposed to think B. hamifera is not truly 

 indigenous to Britain. It has frequently occurred to me that 

 the algal flora of many parts may be temporarily, or even per- 

 manently, enriched by the unwitting agency of man. The com- 

 mon algae which grow on the submerged portions of ships may 

 very well harbour the spores of plants, although the plants 

 themselves could not survive the voyage. Moreover, small 

 portions of some algae might possibly endure the changes. The 

 spiral base of one of my specimens (Fig. 6) suggests the possi- 

 bility that the curious hamose branches, in the absence of other 

 means, may propagate the species. This is not altogether with- 

 out analogy in the Florideoe. Dr. Bornet states that portions 

 of the thallus of Polysiphonia furcellata Harv., and P. atro- 

 rubescens Grev., become detached and are capable of growing 

 into plants.* 



* "Les Algues de Sehousboe " in "Mem de la Soc. des Sci. Nat. et 

 Math, de Cherbourg," T. xxviii., p. 311. 



