DISTRIBUTION OF ALGJE 31 



The laminarian zone extends from low- water mark to the depth 

 of fifteen fathoms. The Laminariacece and the beautiful red algae 

 (Floridece) grow here. 



The third or coralline zone extends to the depth of about fifty 

 fathoms. The algae of this zone, the nullipores, are incrusted 

 with a deposit of lime which gives them the appearance of corals ; 

 and, singularly enough, the corals, which are animal forms, 

 simulate plant life. 



Again, algae have special habits and demand certain climates 

 and seasons for their growth. Algologists register the place 

 where a specimen is found, and in this way localities have been 

 pretty well determined. However, great exactness has not been 

 reached, and the collector is ever watchful to find an alga in 

 some undiscovered home within the given range. Although 

 algae grow from extreme high- water mark to the depth of fifty 

 fathoms, almost every variety may be found on the beach, those 

 growing in deep water being frequently torn off and washed 

 ashore by the waves. The heaps of sea-wrack will often reward 

 one who examines them carefully for deep-water species. . Sea- 

 weeds are most abundant on rocky shores, particularly where 

 there are stratified rocks with crevices, which afford shelter from 

 the waves. Rock pools often contain beautiful varieties of the 

 more delicate species. Red algae will sometimes be found on 

 the shady side of these pools. Sand-beaches are unfavorable 

 to the growth of seaweeds, but fronds which have been carried 

 long distances by the currents will frequently be found on such 

 shores. 



