274 THE NATURE-STUDY REIVE II' [ 2 :8-nov.,i 9 o6 



(e. g. Wilson's snipe) is probably to be found in the extreme famil- 

 iarity of the names, and a mistaking of knowledge of name for knowl- 

 edge of the bird itself. 



The third column requires but a single comment. This does not 

 show so accurately as the first column the commonness and conspic- 

 uousness of the birds in the field, for a part of the course was 

 devoted to laboratory identification of stuffed specimens. Thus, for 

 example, the rose-breasted grosbeak is far from common in the near 

 neighborhood of Delaware; but the plumage of the male is of such 

 a character as to impress the laboratory specimen upon the attention 

 of almost every member of the class. Only three students were 

 familiar with this bird at the beginning of the course 102 at the end. 

 The conditions are similar in the case of the scarlet tanager and the 

 cedar waxwing, although both are locally much commoner than the 

 grosbeak. 



In Table 2 the data are considered from the other point of view, 

 the number of birds known by each student. The tabulation is largely 

 self-explanatory and there is need of little comment beyond the em- 

 phasizing of a few interesting points. The data for the men and 

 women are first plotted separately (I and II) and then combined in a 

 curve for the entire class (III). In each case abscissas [horizontal] 

 indicate numbers of birds known; ordinates [vertical] percentages of 

 men, women, or entire class respectively. The solid lines represent 

 the conditions at the beginning of the course, the broken lines at the 

 close. 



The curves for the beginning of the course are the more important 

 and will be first considered. Because of their more active out-door 

 life, the men would naturally have a more extensive knowledge of the 

 birds than would the women; and this is clearly shown by a compari- 

 son of the curves I and II. While the apex of the curve for men 

 shows a maximum number (24 per cent.) knowing from 31 to 35 

 species, the corresponding apex for the women (representing 31 per 

 cent.) falls in the column indicating a knowledge of only 11 to 15 

 species. 



In curve III for the entire class the double maximum is easily 

 explained from the co-educational character of the class, the one 

 maximum being determined by the men, the other by the women. But 

 a very curious fact comes to light in that the separate curves for men 

 and women (I and II) both show somewhat similar, though less strik- 

 ing, double maxima The curves are based on somewhat scanty data, 

 and the secondary maxima may be merely accidental; but another 



