542 



BULLETIN OF THE BUREAU OF FISHERIES. 



Chart 272. — Distribution of algae on Spindle Rocks, September 2, 1905. 



The rocks on September 2 presented an aspect similar to that on July 22 (chart 271) with some 

 features, however, more pronounced. The prevailing green alga was Ulva Lactuca var. rigida (5) form- 

 ing large patches on the tops of rocks. The most conspicuous brown algae were Chordaria flagelliformis 

 (28), growing in large masses, sometimes as a zone below low-water mark (the dotted line), and old 

 Scytosiphon lomentarius (26) forming patches higher up on the rocks. The most conspicuous zone (much 

 more pronounced than in chart 271) was that near low- water mark composed of Ceramium rubrum (43) and 

 Polysiphottia violacea (48). There was much less Nemalion mullifidum (40), which, however, formed a 

 zoneonrocks V, VII, and VIII. Chondrus crispus (49) was plentiful in deeper water belowthe Chordaria. 



List of algae: Calothrix scopulorum, 1, small patches on barnacles and rocks; Rivularia atra, 2, on 

 barnacles; Ulva Lactuca var. rigida, 5, plentiful on tops of rocks; Enleromorpha crinita, 6, few plants; 

 Enter omorpha prolifera, 8, few plants; Ectocarpus confervoides, 14, on old plants of Scytosiphon; Ecto- 

 carpus fasciculatus , 15, abundant on Chordaria and Chorda; Scytosiphon lomentarius, 26, patches of old 

 plants; Chordaria flagelliformis, 28, abundant; Chorda filum, 31, large patches; Laminaria Agardkii, 33, 

 occasional plants; Fucus vesiculosus, 35, scattered plants; Porphyra laciniata, 37, scattered plants; Nema- 

 lion multifidum, 40, abundant; Callithamnion Baileyi, 41, many on Chordaria; Callithamnion corym- 

 bosum, 42, many on Chordaria; Ceramium rubrum, 43, very abundant; Dasya elegans, 45, occasional 

 plants-; Polysiphonia violacea, 48, very abundant; Chondrus crispus, 49, abundant; Champia parvula, 

 50, occasional on Chordaria and rocks. 



