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F. — l know Saturnia Volypliemus is found here^ and I 
think it probable ^S*. Luna too ; both of them splendid moths. 
Here are the first signs of returning spring that I 
have yet seen in the vegetable creation. The catkins of the 
Poplar {Topulus Tremuloides), and those of some of the 
Willows {Salix), are just beginning to show their silky 
heads out of their bursting envelopes. These trees, like 
many others^ blossom before they put forth their leaves ; the 
catkin^ or amen t, as it is botanically called, being a spike of 
close-set^ minute flowers. Both of these genera, the poplar 
and the willow^ have the male and female flowers on differ- 
ent plants, but the catkins resemble each other. Of the ge- 
nus Salix, Professor Eaton gives, in his excellent Manual 
of Botany/* no less than forty species as indigenous to North 
America. They chiefly delight in wet places, but do not 
abound in the primitive forests. Of all the plants in this 
class, fertile seeds can be produced only by the proximity of 
the two sexes, so that the farina from the stamens may im- 
pregnate the pistils. Common as that graceful species, the 
Lombardy Poplar {Pop, Dilatata) is, both here, and all over 
the United States, it is said, that no pistillate or female 
plant of this species has ever been brought to America, and 
consequently, being all males, no seed has ever been produced 
here. 
C. — How have they then been multiplied ? 
— By suckers or shoots, which take root very readily ; 
but as these twngs or suckers, however recently inserted, 
feel the effects of age in the same degree as the twigs remain- 
ing on the original tree, the species is becoming enfeebled 
with age in our country, so that very recent shoots will 
hardly withstand a severe winter. We see but the feeble 
limbs of an exile in dotage, though yet sustained in a thou- 
sand localities." 
C. — I have lately observed several caterpillars, thinly 
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