FOREWORD 



Many of the data on the dimensions of flying animals are found in 

 journals which are not readily accessible. Aside from Sotavalta's pa- 

 pers on insects, published within the past 15 years, the significant refer- 

 ences are also many years old, harking back to an era when such studies 

 were undertaken primarily to provide inspiration for the development 

 of aircraft. 



The literature is quite extensive for insects, for birds, and even for 

 bats. Furthermore the results of the several investigations appear con- 

 sistent among themselves, leading to the presumption that a reasonable 

 degree of precision obtains for all the great mass of available data. 



It seemed worthwhile first to bring these scattered sources together 

 in one publication, and second to plot the various dimensions against 

 each other to determine how well the principles of dimensional similar- 

 ity hold for so diverse a collection of flying animals. The figures speak 

 for themselves. The text has been added by way of summary and to 

 point out certain anomalies which appear to provide exceptions to 

 nature's usual sense of orderliness. The scientific names in the tables 

 are given as they appeared in the original publications, in the belief 

 that few identification difficulties will arise. 



There is no claim to originality in what follows. I shall be quite con- 

 tent if it is useful, perhaps even stimulating, to entomologists and 

 ornithologists. 



Crawford H. Greenewalt 

 Greenville, Delazvare 

 November 1960 



