BIOLOGICAL EVIDENCES OF UPLIFT 41 



was often an indication of an uplifted section of shore even before the 

 other correlated evidences were discernible. They are very commonly 

 partly hidden by annual plants, and even by alder bushes with from one 

 to five annual rings (see plate 17, figures 1 and 2). 



Very often the barnacles were found on boulders on a beach, and it 

 may be pointed out that while such occurrences might be critically rejected 

 as evidence of uplift, because stones covered with barnacles could be 

 thrown up by waves such as accompany earthquakes, in all cases where 

 such occurrences were noted, barnacles were found adhering to adjacent 

 rock cliffs or benches at equally high levels — positions which would pre- 

 clude such objection. 



These barnacles were an important feature in this study — first, because 

 they initially called our attention to the fact of the deformation ; second, 

 on account of their function as a quantitative measure of its amount, as 

 stated below. The fact of the presence of dead barnacles fixed to the rock 

 in the midst of grasses and shrubs early attracted our attention. From 

 that we went to the physiographic forms, not well developed on the site 

 of our first observation, and from that to other physiographic evidences, 

 to other biological evidence, and to the human testimony. 



MUSSELS 



Equally widespread in the fiord, though less abundant than Balanus, 

 is the common mussel (Mytilus edulis, L.) ; and its shells constitute an- 

 other of the characteristic fossils on the upraised strand. These mussel 

 shells, which turn blue when exposed to the air, were first observed from 

 a boat in Disenchantment bay in clusters about 18 feet above tide water, 

 when we supposed them to be clusters of b.ue flowers growing in niches 

 in the rock. . Later their true nature was determined, and it was found 

 that both there and in many other parts of the fiord the mussels were still 

 clinging to the rocks by their hair-like byssus (see plate 17, figure 2), 

 another evidence of the recency of the uplift. Mytilus, though often 

 present, was not used in measuring elevations, partly because barnacles 

 were always found where any marine life clung to the rock, and partly be- 

 cause the mussels were much less frequently attached than the barnacles. 



BRYOZOANS 



Below low tide, and in permanent tidal pools, there grows along the 

 shores of the fiord a pink bryozoan, forming a film on the rock, which 

 on exposure to the air turns white. On those parts of the coast which 

 were upraised more than 10 f eet, patches and bands of this bleached organ- 

 ism clinging to the upraised cliffs form a prominent feature, often visible 



