FEUCTIFICATION OP SEA- WEEDS. 33 



magniiSed ; and fig. 2, a capsule of the same greatly mag- 

 nified. Tliis elegantly urn-shaped capsule is also called a 

 ceramidium, a name applied to a capsule furnished with a 

 terminal pore or opening, and containing a tuft of pear- 

 shaped spores. Now by looking at the greatly magnified 

 capsule or ceramidium, you will see that it is open at the 

 top, and that it contains the tuft of spores or seeds. This 

 FolysipUoyila with its capsular fruit is very common every- 

 where. 



We next exhibit, at B, the granular fruit of this same 

 P. ttrceolata, no less common. Figure 1 is a portion of a 

 branchlet, with the granules imbedded in the upper half ; 

 and these are called tetrasj)ores, because, when much magni- 

 fied as in fig. 2, they are found each to consist of four spores 

 or seeds. You observe also in the branchlet, the joints and 

 the longitudinal tubes or siphons. 



At C, is the representation of two kinds of fructi- 

 fication found on a very common, but beautiful plant, 

 Ptilota i:)lmnoHa. Pig. 1 is an involucre containing fa- 

 vellse ; fig. 2, a lacinia, with tetraspores on short pedicels : 

 magnified. 



At D, two kinds of fructification of the beautifid Ploca- 

 muni coccineum are represented. Tig. 1, a branchlet with a 



D 



