

)^.c 



l\TI(( HHCTK >\. 



The following preliminary remarks Diay prove interesting to 

 those who have oot heretofore paid much attention to the subject 

 which has inspired the preparation of this volume. 



The term .1/'/" signifies v i and is used u> designate 



certain marine and fresh-water plants, which because they bear do 

 flowers, stamens nor |>i-til-, :m<l in fructification produce spores 

 instead "l seeds, are styled cryptogamous plants. The Alga < <> i n - 

 prise qoI "iilv sea-weeds properly so-called, I n 1 1 likewise the 

 gelatinous, or scum-like substances found floating on or Dear the 

 surface of ponds, ditch water and placid streams; only a verj 1 1 1 : 1 1 1 

 proportion "l the entire class "l fresh-water Alga; in confined t<> 

 i run k- of trees, shady recesses, or i" rocks dripping with moistun 



(win.: in the life-like |>eculiarities exhibited in some stages of 

 their development and growth many of the Alga wire believed 

 l>\ KIuviiImtl: and other aiicroscopists of his time, to belong t > the 

 animal kingdom, but the wholly vegetable character of the Alga is 

 dow i<"' well established t" admit of further controversy. 



Howsoever great in other respects, their individual different 

 may be, the Alga possess certain characteristics which are common 

 n> them all. The> are cellular, flowerless :in<l devoid of root-: 

 their home is in the water ; the ven t<-\\ which affect other localities, 

 die when deprived of moisture. Their nutriment is absorbed through 

 their entire surface from the medium in which they live, liny 

 are totally devoid of vascular tissue, in fact, are merely congeries 

 of simple cells on the arrangement <>t" \\ hich depends their structural 

 different 



\'\\ classes of plants present greater diversities of form than >\<> 

 ill.- .{/<; Some are minute enough to tax the powers of our h st 



