336 Correspondence. [q"| c 



CORRESPONDENCE. 



Parasites of Birds. 



To the Editors of 'The Auk': — 



Dear Sirs: — An interesting note by Dr. R. W. Shufeldt in the April 

 number of 'The Auk' suggests that other ornithologists might be interested 

 in knowing where to find descriptions and figures of the parasites which 

 occur upon birds. For the group of Mallophaga, which is the principal 

 group of insects infesting birds, there is a very extensive and exhaustive 

 monograph in French by Piaget entitled 'Les Pediculines,' which, with 

 supplement, covers practically everything that is known regarding syste- 

 matic arrangement and descriptions of these parasites as well as of the 

 suctorial parasites of mammals up to date of publication of the supple- 

 ment, about seven years ago. A few papers by the same author and by 

 Neumann have appeared since then and the writer has given a short 

 account of the species affecting domestic animals, also describing some 

 American species, in Bulletin Number 7, of the Division of Entomology, 

 United States Department of Agriculture. 



Of the earlier works on these parasites those of Nitzsch and Denny are 

 important, the latter being in English and covering the species known to 

 occur in Great Britain. This was published in 1842 and is, of course, 

 deficient in regard to the recently described species. Another work, the 

 'Epizoa,' by Geibel, in German, contains full accounts of the species 

 known up to 1872, with colored plates for a large proportion of them, and 

 is quite serviceable for the study of these parasites. The work by Piaget, 

 however, is most essential. 



In regard to photographing these insects it has been my experience 

 that it is a difficult matter to get photographs which give distinct details 

 of the minute parts, some of which are particularly necessary for the 

 discrimination of the species, although the photographs will give a 

 general outline and certain portions very distinctly. If the photograph 

 is made with transmitted light certain portions, especially where the 

 tissues are denser, will appear obscure, and most surface characters are 

 lacking, and with reflected light it is impossible to get photographs from 

 specimens in balsam, and if taken from unmounted specimens there is 

 much difficulty in getting the parts all into focus so as to secure a distinct 

 outline as well as clear details of the surface markings. These parasites 

 can be studied very nicely with a compound microscope with powers 

 ranging from 50 diameters to 200 diameters, and if the specimens can be 

 examined while alive some of the structures otherwise obscure are likely 

 to be discovered. In preserving them it is well to put a number in 

 alcohol in small vials with note giving name of host, and if the material 



