198 THE AMERICAN NATURALIST. (Vor. XXXV. 
been differentiated into calyx and corolla. It is either want- 
ing, or is represented by a number of small scale-like bodies, 
indefinite in number, sometimes present in the staminate and 
replaced by bracts in the pistillate flowers; or it may be so 
ambiguous as to leave its morphological significance in doubt. 
Gradually in the rise of the flower from its primordial stage 
the perianth becomes more and more important, until in the 
pink family, which occupies an intermediate position, the 
corolla is large and conspicuous. The flowers are very gen- 
erally wind-fertilized, and, as may be observed in the grasses 
and sedges, this is not favorable to the high development of 
the floral envelopes. Mechanical difficulties are also presented 
by the aggregation of the flowers in a dense inflorescence. 
For instance, in the staminate ament of the alder, where the 
calyx is present, I found by actual count in an ament two and 
a half inches long seventy-seven flowers; while in the stami- 
nate ament of the willow (S. discolor), of about half this length, 
there were two hundred an seventy flowers, or seven times as 
many flowers to an inch in length. There is no room for 
a perianth, and the office of protection has been assumed by 
scales and woolly hairs. 
Though the larger part of the families are anemophilous or 
self-fertilized, their coloration is highly interesting as showing 
what colors the bracts and perianth would develop naturally as 
the result of chemical and physical influences, and in a limited 
number of cases the effect upon such flowers of insect visitors 
at a later period. 
Lowest in rank of the choripetalous series stands the order. 
of the Piperales, with perfect flowers in slender spikes destitute 
of a perianth, and divided, according as the carpels are sepa- 
rate or distinct, into the Piperaceze and Saururacex. The 
former is a tropical family, but the latter is represented in 
eastern America by Saururus cernuus, lizard's tail, a name sug- 
gested by the slender spike with drooping apex. The flowers 
are fragrant, with white stamens, and probably attract insects. 
A large number of shrubs and trees have the flowers in 
aments and are frequently referred to as the Amentacez. 
They are widely distributed throughout the temperate and 
