60 



are pear-shaped bodies, of tbe simplest possible structure, and 

 at the apex of each are either tivo ox four cilia or short thread, 

 like processes. fYou will observe, by the way, how the parts 

 of these simple plants always seem to run into some multiple 

 of Jour : just as in the far more complicated endogens the 

 multiple of three and in the exogens of four or five, is the 

 rule.) 



As soon as the Zoospoore is at liberty, it begins to rove 

 rapidly about by means of its cilia, which are lashed violently 

 and so produce a current in the water. After a time, (when 

 I suppose it has sown a sufficiency of wild oats) it settles down 

 on some fixed object, attaches itself by its pointed end, drops 

 its cilia, and at once vegetates into an Algae — thus affording 

 in its life history a striking parallel to that of the Cirrhipeds 

 (or Barnacles), among Crustaceans which have so long been a 

 stumbling block to the disciples of Darwin. 



Eising by gradual stages from the Oscillatores and their 

 allies we reach the Confervacea — a conspicuous member of 

 which is the matted specimen on the table. The members of 

 this order consist of simple or branched filaments, divided 

 into or rather made up of numerous cells of simple construc- 

 tion, filled with granular bodies, often disposed in elegant 

 patterns, as may be seen in the species of Spirogyra, very 

 common in our lagoons and waterholes. Confervacea exist in 

 abundance in both fresh and sea waters, where they may be 

 seen either in large shapeless masses or waving in the stream 

 like bundles of light green silk. 



How many species we may have in Tasmania, I know not, as 

 the subject has never been investigated, though one well worthy 

 the attention of some microscopist with plenty of time and 

 patience at his command. Dr. Hooker (in his great work on 

 the Tasmanian flora), mentions three marine Confervse ; and 

 adds, " We have received specimens of several freshwater Con- 

 ferva from Mr. Gunn unfortunately not in a state fit for 

 examination or description." 



Two species are common in Great Britain, and are (I 

 believe^, universally distributed throughout Europe, viz.: — 

 Conferva homhycina and Conferva fioccosa, both determined 

 by the great Swedish Algologist Agardh. It is to one of 

 these, as we have seen by his letter, that Baron von Mueller is 

 inclined to refer our specimen. 



And if we are ignorant of the species, equally so are we of 

 the cause of the combining together of the filaments into the 

 curious paper like structure, which you see before you. I have 

 often found on the edges of ponds and slow streams in 

 England the thick blanket like strata of matted Conferva, to 

 which the Baron draws our attention, and which are vulgarly 

 styled " water flannel " in the old country. But these are 



