10 
Indiana University Studies 
sort; such physiologic characteristics as can be shown to be hereditary 
and subject only to such environmental modifications as may be meas- 
urable; such special physiologic characteristics as are more often classi- 
fied as psychologic, or as elements of “behavior”; and whatever other 
measure there may be of the physico-chemical organization which is the 
hereditary basis of the organism. This, in brief, demands a biologic as 
well as a structural basis for the recognition of species. 
5. The special consideration of individual variation, with an at- 
tempt to analyze the hereditary or non-hereditary basis of the unusual 
characters. Many of the older workers made it a practice to throw 
their “exceptions” into the waste basket! 
6. The accumulation of data with due scientific caution, and the 
further preservation of data in the form of labelled specimens, with the 
detailed citation of all such data in publication. In this admirable item 
of technic, taxonomy has been in advance of other fields of biology. 
7. The classification of the species of the group to show every 
recognizable degree of phylogenetic affinities, the interpretation to be 
based on the above criteria for the recognition of relationships, upon 
host affinities (if available), the facts and known factors of geographic 
distribution, and correlation with the known geologic history of the area 
involved and the paleontologic history (if available) of the group and 
all closely related groups. 
8. The interpretation of biologic phenomena within the group by an 
appeal to this phylogenetically established classification, to show the 
occasion and the order of evolutionary origin and the conditions of ex- 
tension of the phenomena exhibited within the group. 
9. The careful consideration and utilization of findings from other 
fields of scientific research at every step of the taxonomic investigation. 
The above program is an ideal not always obtainable even 
with the best of modern facilities, albeit a standard by which 
the merit of a piece of taxonomic work may be adjudged. It 
demands the intensive treatment of such small groups of spe- 
cies as genera or families in contrast to the wider fields of 
interest of the older systematists. It calls for the so-called 
revisional treatment of genera instead of the miscellaneous 
species descriptions of long repute. It demands that phylo- 
genetic units, instead of local faunas or floras, be the basis of 
taxonomic consideration. It demands that the taxonomist’s 
role as the diagnostician of specimens emanating from en- 
thusiastic collectors and hard-pressed economic entomologists 
be subordinated to the phylogenetic interpretation of biologic 
phenomena. 
