(42) 



time of appearance, as residents, migrants, etc., are in common use, and 

 with prettj' definite meanings. But no terms denoting number are in use, 

 or, so far as the author can learn, have ever been proposed. With the end 

 in view of suggesting such terms the labor of preparing this paper was 

 begun. 



First the dictionaries were searched for words with exact significance 

 as to number, but none were found. It was evidently necessary to ascribe 

 to the tenns selected arbitrary meanings. In making this selection it seem- 

 ed to the author that the following should be avoided: Awkward express- 

 sions; negative terms, as ?iot common, not rare, etc.; terms unfamiliar in 

 ornithological literature, as sparing, few, etc.; terms commonly associated 

 with other ideas than that of number, as copious, plentiful, etc.; and final- 

 ly the use of indices or subscripts seemed unwise as savoring of the techni- 

 cal, and not likely to commend itself to the majority of observers. In the 

 eight state and sectional lists only the words common, abundant and ra/r 

 were used by all, occasionally by five, and scarce, freguetif, numerous and 

 uncommon each by only two. Common appeared in combination with nine 

 adjectives, rare with five, ntinierous with five, and abundant with four. At 

 first it appeared desirable to avoid entirely the use of qualifying adjectives, 

 but a sufficient number of good words did not seem available, so the writer 

 fell back upon the use of the adjective very, which was the one most used 

 by the authors of the lists previously mentioned. 



The number of words to be employed and their significance was the 

 most serious problem of all, and here the otily aid at the command of the 

 writer was found in the "bird horizons" published from time to time in the 

 Wilson Bulletin; so that any suggestions along this line must be merely 

 tentative, and subject to change after a practical application of the scheme 

 here proposed. In the attempt to formulate a scheme, the mile and the 

 square mile presented themselves naturally as the units of linear distance 

 and area, while the numbers 1, 2, 5, 10 and 20 were decided upon as an easj' 

 series to remember, and as having an appropriate relationship to one 

 another, so far as could be judged from the above lists. Owing to the 

 greater abundance of birds during mig-ration when the linear distance 

 would be most used, while in a formal treatment of the birds of a given lo- 

 cality the areal unit would be employed, it seems possible to adopt the 

 same series of numbers for both cases, applying them in a slightly differ- 

 ent manner. 



The result is embodied in the following table of meanings: 



