VOL. IV.] Tar and FeatJiers. 365 



seem to be the birds most eflfected in the region of San Diego, 

 but all of the common species are apt to show black blotches at 

 times. For a long time after the condition was first noticed I 

 was at a loss to account to my own satisfaction for the origin. 

 The theory that the birds had been feeding about the carcass of 

 a whale or seal and gotten their plumage greasy from that or other 

 sources was anything but satisfactory in view of the appearance 

 ■of the stain and the species affected. Western grebes and Pacific 

 fulmars — white phase — were sometimes seen with the entire 

 lower plumage matted into a solid black mass, and not infre- 

 •quently such birds were found dead on the beach. Whether their 

 death was caused by the condition of their plumage I am unable 

 to say, but from the appearance of some of the worst cases I 

 should say that it probably had something to do with it. 



As such specimens were so obviously worthless I have carefully 

 avoided them, and until the present season my observations were 

 limited chiefly to the living birds and those but little affected. 



On July II of the present year, however, a Piiffinus griscus 

 was shot off San Diego and while the feathers of the left side 

 and flank were glued together in a solid sheet it was by far too 

 ■desirable to discard on that account, and an effort was made to 

 save it, and after a liberal application of gasoline it was admitted 

 to the cabinet minus a part of its plumage that was uncleanable. 



This specimen — the first that had fallen into my hands in a 

 condition suitable for examination — explained very clearly the 

 mystery of the many stained plumages; it was due solely to a 

 sticky, soft mass of asphalt. 



I have frequently found small blotches of this substance 

 varying from the size of a postage stamp to several inches or a 

 foot in diameter floating about on the surface of the sea, evidently 

 coming from some submarine source to the north, where the 

 oil shales reach the Coast in the region of Santa Barbara. 



This substance when it first comes to the surface contains 

 enough volatile matter to render it about the consistency of 

 molasses, and cause it to stick to anything with which it comes 

 in contact. As the volatile gases escape it becomes hard and 

 tough, encasing the bird that is so unfortunate as to swim into 

 a floating mass in a coat more suitable for a turtle or armadillo 

 than a member of the feathered kingdom. 



