HOW TO KNOW THE SEAWEEDS 



182a Branching sympodial, the branches of each order unilateral and 

 pectinate. Fig. 228 Plocamium 



Fig. 228. Plocamium pacificum 

 KyUn 



A portion of a plant, X 1. 

 This is a common and very at- 

 tractive, delicate red alga along 

 the Pacific Coast. Throughout 

 its range it is often accom- 

 panied by a smaller and more 

 purplish colored species, P. vio- 

 iaceum Farlow, which, however 

 does not at all compare in the 

 frequency with which it will be 

 noticed by either the casual ob- 

 server or the professional col- 

 lector. So handsome and of 

 such interesting geometric form 

 is Plocamium. that one finds 

 himself making extra speci- 

 mens simply for their esthetic 

 value. Indeed, it has been em- 

 ployed in the making of attrac- 

 tive, decorative greeting cards. 



Although P. pacificum is oc- 

 Figure 228 cosionolly epiphytic, it is usu- 



ally foimd massed on rocks at 

 low tide level and below, con- 

 spicuous by its rich rose-red 

 color, and often of moderate size, 10-25 cm. tall. It extends on down 

 into deeper water, becoming more laxly branched in depths of 20 to 

 25 feet, and even more brightly colored. 



182b Branching monopodial, the branches not unilateral. 



183 



172 



