THE AMERICAN BOTANIST. 
93 
fallible signs of these simpleminded people and others who 
claim to have made a study of the matter are : the thickness of 
one season's growth of bark on the hickory, oak and maple 
trees ; the size and number of cones on the pine and hemlock ; 
the abundance or scarcity of berries of certain species of plants ; 
the thickness of corn husks and the outer shell of the hickory 
nut and many others. There are also many ''signs" relating 
to weather conditions applying to Zoology. These people 
claim, and with some degree of assurance no doubt, that until 
the science of Heterology becomes more exact they have as 
good ground for predicting in a general way what is in store 
for us as our paid weather man. It might be interesting and 
perhaps of some value if some one would compile a list of 
these so-called ''signs" as far as they relate to Botany. Could 
we not have, through the medium of the Botanist, different 
observed coincidents between plant life and immediate or re- 
mote weather conditions ? — Earl Lynd Johnston, Evans, Colo. 
Range of Monarch Butterfly. — Not a few kinds of 
plants are so dependent upon insects for pollination, that their 
very existence may be said to be bound up with the success of 
a single insect. Should the latter thrive, the plants flourish 
and spread to new regions; should the insect fail, the plants 
decline and perish. As is well known the plant covering of 
our earth is constantly changing and it is no suprise to find that 
the struggle for existence is quite as fierce among the insects. 
The common monarch butterfly (Anosia plexippus) the large 
red-brown insect common in late summer, whose larva feed 
upon the milkweed ( Asclepias) is a sort of an English sparrow 
among the insects and has spread over a large part of the 
earth. According to Kellogg's "American Insects" it has 
spread over all of North and South America, the Hawaiian 
Islands and Samoa, and has also gained a foothold in Western 
Europe. Who knows what plants it has made rare by crowding 
out the insects that pollinate them? 
