196 THE ANIMAL KINGDOM. 



1, The stichidia, or oblong vesicles containing spores in 

 separate divisions or cells very beautiful. 



2, Spherical capsules, seated upon the branches, contain- 

 ing a cluster of spores. 



This is a common Sea-weed everywhere in Summer and 

 Autumn. 



POLYSIPHOXIA. 



There are twenty-four species of this Sea-weed, some of 

 them inhabitants of the rock-pool, some of the wide wild 

 ocean, growing on the stems of Laminaria, and therefore 

 often found upon the beach after a storm, or obtained by 

 dredging on all the British coasts. It also loves to grow 

 upon Melobesia on the steep sides of rock-pools. 



Of all these the P. urceolata and P. elongella are the 

 best for microscopic observation. The former has a beau- 

 tiful fructification; an urn-shaped capsule called a cera- 

 midiunij furnished with a pore or opening like the mouth of 

 a vase, and containing a tuft of pear-shaped spores. 



A second form of fruit is met with on the same plant 

 the tip of a branch expands, and a row of tetraspores is 

 imbedded in it ; also on Polysiphonia fastigiata such an 

 abundance of antheridia is found as to give a yellow 

 colour to the plant, quite visible to the naked eye, and de- 

 serving particular microscopic observation. 



SPHEROCOCCUS. 



A common plant, often cast ashore after a gale, and 

 found all along the coast of Cornwall and Devonshire, Isle 

 of "Wight, and the Channel Islands. 



It is difficult to obtain perfect specimens of the beautiful 

 fructification, they are so often destroyed by the violence of 

 the waves ; but a careful dissection of it freshly gathered 

 would be both delightful and instructive. 



We find minute spherical capsules supported on slender 

 stalks and mucronate, that is, having a little spine ob- 

 liquely projecting from their apex ; upon opening this, by 

 making a section through it, we see a cluster of crimson, 

 seeds, also stalked. The structure of the branches should 



