480 
in classifying these insects is the condition of the carinae on the 
frons, whether there be one simple carina, or if it be forked, 
or if there be two. These conditions are found quite indepen- 
dent of one another in different families and in groups in the 
same family. The condition of the antennae is also used in some 
families, and here again there is no phylogenetic connection be- 
tween those having large, flattened antennae, as they are found 
in more than one group of a single family (i. e., Delphacidae ). 
In the Derbidae we find the sub-antennal process and shoulder 
keels developing quite independently, and the latter forming a 
large antennal chamber in widely separated genera. It may be 
objected that the present classification of these families is not 
“natural,” and hence the apparent homoplasmy, but 1n whatever 
sequence or order these genera may be placed, cases of homo- 
plasmy will be found. 
This condition is not peculiar to the fulgorids, but is found 
in every group of insects of moderate size which one studies. 
Timberlake, in discussing a single family of Hymenoptera, the 
Encyrtidae, remarks: 
‘‘The bewildering plasticity of the group whereby the same character 
may have been developed independently in different genera (as, for in- 
stance, the fascicle of hairs at the apex of the scutellum in Encyrtus, 
Cheiloneurus, and Chrysoplatycerus.) ’? * 
These few cases of homoplasmy, out of vast numbers which 
could be cited, have not been brought to your notice out of idle 
curiosity, but because | believe that they are important evidence 
in the one great problem which should be at the back of all 
zoological studies, viz., evolution. 
Although I appreciate and admire the vast amount of experi- 
mental zoology that has been done within recent time, yet, when 
it is all considered, it does not give direct or indirect evidence 
enough to base a belief in evolution upon. This belief is based 
upon nature's own experiments, upon our studies of develop- 
ment, comparative morphology and anatomy of living and fossil 
animals, upon the geographic distribution in past and present 
time, and the time sequence as shown by fossils. Most of this 
information is the direct result of systematic zoology. If all 

* Timberlake, Proce. Ent. Soe. Wash. 25 (3), p. 58 (1923). 
