204 Ge7ieral Notes. \_h'%. 



of strong flight, and the body feathers are very apt to precede in their 

 growth the remiges and rectrices, although in the two specimens cited, 

 the rectrices are already partly renewed. The third specimen (Phila. 

 Acad. Nat. Sci., No. 15661, French Guiana), is unfortunately undated, but 

 it is evidently passing from the juvenal plumage by what must be called 

 a postjuvenal moult. The worn' first primary, inner secondaries and a 

 few of the rectrices, together with a green-tinged back, indicate a young 

 bird. The crown now worn brown also indicates juvenal plumage, while 

 new feathers are breaking from their sheaths, both on the head and 

 throat. These birds all bear out my conclusion that adult Swallows 

 moult earlier than j'oung birds which undergo a complete postjuvenal 

 moult, often in midwinter. It is, on the whole, expedient to speak of a 

 postjuvenal moult and not of a prenuptial, even in those species which 

 are late in assuming a first winter dress, which then becomes that of the 

 first summer simply through wear. This sequence of plumages obtains 

 largely both amohg the North American Hirundinidae and Tyrannids, 

 and I am glad of this opportunity of calling attention to it. 



I would also correct here a slip of Mr. Stone's pen at page 118 of his 

 review in ' The Auk,' where he has inadvertently credited the Cross 

 bills with a " prenuptial " moult, meaning of course, the postnuptial. — 

 Jonathan Dwight, Jr., New York City. 



To Remove Fat from Bird Skins. — Fat on sea and water birds is 

 especially difficult to get rid of. It means long and tedious scraping, often 

 with unsatisfactory results. Benzine, sulphuric ether, alkalies and other 

 solvents of grease and oils, are either unpleasant to use, dangerous in a 

 room with fire or lamp, evaporate rapidly or are expensive, and after all 

 only dissolve the contiguous layer of fat at each application, often leav- 

 ing the skin in bad condition. 



One day, when almost on the point of throwing away in despair a 

 hopelessly fat specimen, which had been scraped until nearly disinte- 

 grated, and, after having been treated with cornmeal, sawdust and 

 plaster of Paris, still showed oil when pinched, the idea occurred to me 

 of using an absorbent at a sufficiently high temperature to melt out the 

 oil and absorb it at the same time. Some plaster of Paris was put in a 

 bread tin, heated on top of the stove until fairly hot to the hand, and 

 then a thick layer was spread on the bird skin. This was pressed down 

 and inanipulated until a sufficient time seemed to ha\e elapsed, when it 

 was carefully brushed off. The result exceeded my expectation. A sec- 

 ond application practically removed all the oil. Since then I have con- 

 tinued using this method with success. 



The skin must, of course, be first sci-aped so as to break the fat-con- 

 taining tissues and as much fat as possible scraped off, using cornmeal 

 or sawdust as an absorbent while operating. After this the hot 

 absorbent may be applied. The skin may seem very dry after the opera- 

 tion, but this is really only on the surface, and going over it with a damp 



