162 INTRODUCTION TO CRYPTOGAMIC BOTANY. 



mentioned, which are not at all cellular. Many of the gran- 

 ules, according to his observations, are pure starch grains. 

 The genus did not come under the notice of the authors of the 

 memoirs so often mentioned, illustrative of the zoospores of 

 Algae. The best information we have on the subject, is in 

 a paper by Dr. Montague,* who had not, however, the ad- 

 vantage of examining living specimens, Cladothele, a very 

 curious marine Alga from the Falkland Isles, considered by 

 Hooker and Harvey allied to Codiumi, appears to me very 

 doubtful as to its affinities. It is a mass of cells, which 

 alone forbids its approximation ; nor does there seem to be 

 any nearly allied genus amongst the calcareous Algae referred 

 to GonfervaceoB. The point of attachment, moreover, is want- 

 ing, and it is, therefore, uncertain whether it has a mass of 

 rooting fibres. The discovery of the fruit may possibly un- 

 ravel its true affinities. I am half inchned to think that it is 

 a highly compound subcalcareous form of the next division, 

 Ulvaceae. 



135. Vaucheria extends as far south as Kerguelen's Land, 

 where Codiwm also appears, as it does far to the north, the 

 species in both cases, so widely diffused, being G. ionientosum, 

 which occupies also very numerous intermediate stations, while 

 both that and Godium adhwrens occur in New Zealand. The 

 latter is a native of the Cape and Mauritius, as well as of 

 Europe. Gaiderpa, which in the northern hemisphere is 

 strictly an inhabitant of the warmer districts, extends in the 

 south under five species to New Zealand. Bryojjsis also 

 occurs in New Zealand, and as far south as the Falkland 

 Islands, and the seas about Cape Horn. The numerous species 

 of Gaiderpa afford almost the whole sustenance of turtles on 

 many coasts, and other species furnish nutriment to a host 

 of smaller animals. 



12. IJLVACEiE, Ag. 



Cells divided vertically and horizontally, so as to make a 

 frondlike or tubular membrane. Propagation by zoospores 

 furnished with flagelliform cilia. 



* Comptes rendus 26 fevrier, 1838, and Ann. d. Sc. Nat. ser. 2, vol, 

 9, tab. 6. 



