Page:The Gall Wasp Genus Cynips.pdf/16

 sort; such physiologic characteristics as can be shown to be hereditary and subject only to such environmental modifications as may be measurable; such special physiologic characteristics as are more often classified 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 attempt 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 extension 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 species 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 phylogenetic units, instead of local faunas or floras, be the basis of taxonomic consideration. It demands that the taxonomist's rôle as the diagnostician of specimens emanating from enthusiastic collectors and hard-pressed economic entomologists be subordinated to the phylogenetic interpretation of biologic phenomena.