264 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 1 37 



taxonomy and phylogeny have relied upon anatomical, histological, or 

 gross morphological criteria, to the relative exclusion of biochemical 

 or even biophysical methods, in separating taxonomic categories and 

 in making phylogenetic deductions. More often it has been the com- 

 parative physiologist or biochemist who has recognized the poten- 

 tiality of applying his own experimental data to interpretations in 

 these other areas of biology. 



In the case of the present writer, fairly specific interests and objec- 

 tives have led him to observe that the techniques of the physiologist, 

 especially biochemical methods, can be employed to advantage in the 

 attack upon general problems in divisions of biology commonly re- 

 ferred to as "descriptive." For example, in an earlier study, Ford 

 (1941, 1942, 1944), a geneticist with a primary interest in the physi- 

 ology of gene action, observed that the distribution of different pig- 

 ments among the members of one of the largest and most diversified 

 of the lepidopteran families, the Papilionidae, followed a pattern of 

 classification almost identical with that previously established upon 

 structural considerations. Thus, by the use of simple chemical tests 

 for separating different kinds of white and of red pigments, he con- 

 firmed the established taxonomic position of almost 370 different spe- 

 cies of papilionid butterflies, with the exception of several species, 

 the reclassification of which he recommended on the basis of his own 

 chemical and previously described (aberrant) structural features. 

 More recently Micks and Ellis (1952) and Clark and Ball (1952) 

 applied the sensitive analytical techniques of paper partition chroma- 

 tography to qualitative and quantitative amino acid estimation in 

 hemolymph and total body amino acid content, in different species of 

 mosquitoes. The former authors found a striking similarity in amino 

 acid composition of adult female Cnlex pipiens Linnaeus and C. qiiin- 

 quefasciatus Say (thought by some to be subspecies). Clark and Ball 

 compared the amino acid composition of the latter species and were 

 able to separate it from C. tarsalis and C. stigmatosoma on the basis 

 of qualitative differences in such amino acid content. Rockstein and 

 Kamal (1954) have also evaluated the taxonomic position of six 

 different species of flies, by the qualitative and semiquantitative esti- 

 mation of different digestive enzymes in the alimentary tract of their 

 larval forms ; they also interpreted the data obtained in terms of adap- 

 tation by insects with different food habits from scavenger to obligate 

 parasite. 



The writer's interest in the physiological approach to the phenome- 

 non of metamorphosis, especially in holometabolous insects, arose 



