156 LIFE HISTORIES OF NORTH AMERICAN DIVING BIRDS 



assumed in early spring. After perfecting this plumage the young can be 

 distinguished from their parents only by their shorter and weaker bills, by 

 the darker (nearly dead black) coloring of their upper parts, and by the 

 presence of numerous fine but rather conspicuous blackish spots or bars on 

 the tips of the feathers of the sides of the breast and body. 



The sequence of plumages to maturity and the seasonal molts of 

 adults are undoubtedly similar to those of the closely related Xantus's 

 murrelet. It probably does not differ materially in habits from its 

 northern relative. Its northward migration after the breeding season 

 must be more pronounced, however, if we are to refer to this species 

 the well-marked specimens taken by Mr. Adriaan van Rossem (1915) 

 near Los Coronados Islands. 



DISTRIBUTION 



Breeding range. Islands in the Gulf of California. From Cape 

 San Lucas, San Francisco Island, San Jose Island, Ildefonso Island, 

 north to Isla Raza. 



Winter range. Probably near the breeding grounds, but some, at 

 least, "winter" on the Pacific side of Lower California north to 

 Natividad and Los Coronados Islands. As this species breeds in 

 February, the word "winter" is hardly an appropriate term to desig- 

 nate its range during the nonbr ceding season. 



Egg dates. Lower California, Cape Region: 22 records, February 

 6 to April 12; 11 records, February 14 to 24. 



Cepphus grylle (Linnaeus) 

 BLACK GUILLEMOT 



HABITS 



The picturesque coast of Maine is deeply cut by numerous rock- 

 bound bays and harbors, protected by rugged promontories, and 

 dotted with many attractive islands, where forests of pointed firs 

 and spruces grow almost down to the water's edge. It well deserves 

 its popularity, for I can not imagine a more delightful coast for a 

 summer cruise. Not the least of its attractions is this beautiful little 

 "sea pigeon," so common about all the rocky islands and harbors, 

 where it skims away in front of us in a wide circle, flying close to 

 the water, with its trim, little, black body swiftly propelled by the 

 rapid movements of its wings, the white wing patches flashing in the 

 sunlight and the bright red feet showing behind. It is interesting 

 to watch it as it rises from the water ahead of the boat, flying for- 

 ward at first until well 'ahead of us, then swinging in a long curve 

 to one side, and finally dropping into the water again far astern; 

 every bird seems to fly in exactly the same course, almost never flying 



