OUR EXCHANGE TABLE. 
133 
thousands of miles, we are really only hastening a little the 
work of nature, for sooner or later the balance would have 
been restored, the pendulum would have swung the other 
way, and the mighty tribe of Melanoplus differentials 
would have been swept away almost in a breath, leaving 
only a few individuals to begin the work of rebuilding their 
tribe. 
And so the struggle goes on, the insects growing stron¬ 
ger and stronger year after year, until Nature, sometimes 
assisted by man, as in this case, but generally alone, takes 
a hand and the mighty army vanishes and the fields are 
once more green. 
Our Exchange Table. 
Mrs. Annie Trumbull Slosson, perhaps best known to 
Nature Study readers as the author of “ Fishin’ Jim¬ 
my,” but known to naturalists everywhere as an indefati¬ 
gable worker in the field of entomology, contributes to the 
January Entomological News a list of insects taken by her 
on Mt. Washington last summer, and not previously re¬ 
ported from that locality. Mrs. Slosson has reported simi¬ 
lar lists each year since 1893, with the exception of 1900, 
when she was unable to make her customary visit to the 
summit. The present list includes 250 species, several of 
them, and at least one genus, being new to science. 
In his “ Recognition Marks of Birds,” in Bird-Lore for 
November-December, Ernest Seton-Thompson neatly ilus- 
trates an old truth by a new figure when he says of the 
recognition marks of hawks and owls that they are ‘ ‘ to en¬ 
able birds of each species to recognize their friends, just as 
soldiers are uniformed so that each may know his party.” 
Of course, since Darwin, we have understood why the pe¬ 
culiar feature of any species is the most variable feature. 
