THE MUSEUM. 



43 



Tocks near the surf. I have noticed 

 young ones so close to the water that 

 the spent force of a "roller" would 

 almost wash them away. The young- 

 Guillemots are prett}-, fluffy, black lit- 

 tle fellows but they usually keep hid- 

 den beneath the rocks for they seem 

 to inherit that instinct which warns 

 them against exposing themselves to 

 the cannibalistic Gull. 



We come now to the rare Ashy Pet- 

 rel [Oceanodronia HoinocJiroa) which 

 I treated at length in the Nidiologist 

 for August, 1 894 and which I will not 

 repeat. They nest throughout the is- 

 land preferably beneath stone piles on 

 the ground. They fly about only at 

 night. One &^^ is laid which is of a 

 creamy white color both before and 

 after being blown. It is usually but 

 very faintly spotted about the large 

 end and often wholly unmarked. I 

 have but one &gg which is well marked 

 and it has a wreath about the large 

 end composed of irregular dots of light 

 reddish-brown. The eggs of this Pet- 

 rel average considerably smaller than 

 those of Leache's. The measurements 

 of seven eggs are as follows, the ex- 

 treme sizes being given first: I.06X.89, 

 1.22X.89, 1.2OX.89, 1.2OX.87, 1.19x86, 

 1. 1 3x. 89 and 1. 1 ix. 87 inches. 



When one is tired ofscaling the cliffs 

 it is indeed restful to study the spright- 

 ly little Rock Wren [Salpiiwtcs obsolr- 

 tus) as he flits about among the rocks. 

 The island in general is an admirable 

 place for a bird of its habits. At al- 

 most any time during the day the beau- 

 tiful, liquid song of the Wren may be 

 heard from out the barren stone piles 

 as he busily seeks his food. The nest- 

 ing habits of this bird are most interest- 

 ing. The nests are built generally in 

 some deep crevice in the stone walls 



which extend over portions of the is- 

 land. They are composed of fine 

 shreds of farallone weed matted to- 

 gether, with a few feathers intermixed 

 in some cases. One nest at hand is 

 lined with horse and goat's hair. They 

 average three inches in diameter and 

 are loose affairs as a rule. 



The nests being concealed in the 

 stone walls are very hard to discover. 

 I was most successful by walking along 

 the walls and watching closely the crev- 

 ices from which a bird would fly. In 

 the middle of June but two sets of 

 fresh eggs were found, but several 

 nests were discovered containing in- 

 cubated eggs and small young birds. 

 In one place the young were learning 

 to fly. I am informed that the Wrens 

 begin nesting late in April or early in 

 May and I have two sets of eggs taken 

 in August, from which I infer that pro- 

 bably three broods are raised in a sea- 

 son. The habit of paving the entrance 

 to the nest with chips of rock, bleached 

 bones, etc. , is well known. Mr. W. 

 Otto Emerson of Haywards, Cal. , who 

 has collected extensively on the islands 

 has a nest wdth its "ornaments" which 

 is most interesting. Six or seven eggs 

 ' constitute a set early in the year, but 

 the late sets consist of five or six us- 

 ually. 



These constitute the breeding birds, 

 although the American Raven {Cor^'us 

 corax si)utatHs) is present on the is- 

 land and a pair have a nest on an in- 

 accessible cliff, but no one has thus far 

 succeeded in securing the eggs. In 

 June a few Black Turnstones were 

 were seen on the rocks near the surf, 

 and Mr. Osgood noted a Yellow Warb- 

 ler. In winter and spring numerous 

 land birds are noted about the island 



