434 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



has a tendency to grow larger than in more open situations. 

 It is the largest fruticose lichen found on the islands. 



The Cladonias are found, for the most part, under decidedly 

 moister conditions than are the other species of fruticose 

 lichens. C. adspersa and C. Hmhriata were found growing near 

 the top of the main mountain on Chatham Island, along with 

 ferns and other mesophytic plants. At the time the specimens 

 were collected, this portion of the island was heavily enveloped 

 in fog, and on subsequent visits to this locality the same condi- 

 tion prevailed. C. ceratophylla was found under somewhat 

 similar conditions near the summit of James Island. The fourth 

 species in the collection, C. pycnoclada, is found under both 

 xerophytic and mesophytic conditions. It occurs in large tufts 

 on the lava on the west side of the mountain at Tagus Cove, 

 Albemarle Island; and although it is found at a high altitude 

 here, the surrounding vegetation was decidedly xerophytic in 

 character — a condition which on this side of the mountain 

 continues to the top, because this is the leeward side, and is not 

 bathed by the fog-laden wind. It was also found on Chatham 

 Island along with lycopods and ferns, and was taken by Snod- 

 grass and Heller from the mountain at Iguana Cove on Albe- 

 marle Island, at an elevation of 925 m. Although this elevation 

 was not reached at Iguana Cove by any of the members of 

 our party, the conditions there must be very moist, if one may 

 judge from the conditions found nearer the base of the moun- 

 tain. 



Parmelia latissima is the most common of the foliose species, 

 occurring throughout the transition and the moist regions, 

 and often heavily covering branches of trees and bushes, 

 sticks, and dead logs. It was specially abundant about the 

 summit of Duncan Island, where the vegetation is quite open; 

 but in the moister portions of the islands where the vegetation 

 is dense, it is found sparingly. Two other foliose species which 

 occur both in the upper transition and in the moist regions, are 

 Sticta aurata and 5. quercizans, both of which are found usually 

 on the bark of trees ; and while in places they are fairly common, 

 they never so completely cover the trees as does the Parmelia 

 just mentioned. Another species characteristic of both the 

 upper transition and the moist regions is Chiodecton san- 

 guineum, whose conspicuous red thallus is often found adher- 



