"Splitters" and "Lumpers" 



its appendages are black. The wings are bronzy-green. The 

 insect inhabits Mexico and southern Arizona. 



"SPLITTERS" AND "LUMPERS" 



Every true naturalist is called upon to exercise the faculty of 

 discrimination and the faculty of generalization. His work 

 trains him to detect dissimilarities on the one hand and like- 

 nesses on the other. His judgments as to likeness are expressed 

 in the genera, the famiies, the orders, which he proposes. His 

 judgment as to dissimilarities is most frequently expressed in his 

 views as to species. When the two faculties of discrimination 

 and generalization are well balanced and accompanied by the 

 habit of patient observation, ideal conditions are reached, and 

 the work of the naturalist in classification may be expected to 

 stand the test of time. But where, as is often the case, one of 

 these faculties is exalted at the expense of the other, there 

 are certain to result perversions, which will inevitably cause 

 trouble to other students. When a man cultivates the habit of 

 discrimination to excess, he is apt to become, so far as his labors 

 as a systematist are concerned, "a splitter." A "splitter" 

 magnifies the importance of trivial details; he regards minute 

 differences with interest; he searches with more than micro- 

 scopic zeal after the little things and leaves out of sight the lines 

 of general resemblance. Huber, the celebrated naturalist, said 

 that by patient observation he had come to be able to recognize 

 the different ants in a hill, and, as one by one they emerged from 

 their subterranean galleries, he knew them, as a man living upon 

 a certain thoroughfare in a great city comes at last to know by 

 sight the men and women who are in the habit of daily passing 

 his windows. No doubt the critical eye can detect as great 

 individual differences in the lower animal world as are to be 

 detected among men. A student comes to apply himself with 

 great zeal to searching out and describing these differences, and 

 when he undertakes to say that because of them one form 

 should be separated specifically from another he becomes "a 

 splitter." I recall an entomologist whose chief weapon of 

 research was a big microscope. He would take a minute insect 

 and study it until he was able to number the hairs upon its head. 

 Then he would describe it, giving it a specific name. The next 



