1883.] Editors’ Table, 391 
vicianus, Here the male and female resemble each other, the 
sexual character being transmitted in an equal degree to both 
sexes, The only trace of the bars beneath is noticed in the win- 
ter dress of the male. According to Darwin, when the variation 
is sexual, and the adult male molts twice in a season, the winter 
dress resembles the primitive or immature plumage. 
C. ludovicianus var. robustus—The account of the plumage of 
this bird in its different stages is too meagre to serve our purpose. 
It is said to be without wavy bars beneath, and is “tinged with 
ashy laterally and across breast,” in the adult stage. It is probably 
intermediate between /udovicianus and var. excubitoroides. 
It is interesting to note in this connection the range of this 
genus spreading over half a continent. 
The progenitor, dorealis, inhabits “ Arctic America; in winter 
South into the United States, especially into the northern por- 
tions.” Ludovicianus, “ South Atlantic and Gulf States.” Rodustus, 
“ California and fur countries.” xcubitoroides, “ Western North 
America from Pacific coast east a little beyond the Mississippi, 
and to Texas. Nearly all of Mexico.” 
I am aware that this genus has also been modified in other 
ways by natural selection, but only those parts have been chosen 
which serve the purpose of showing their descent through sexual 
selection. 
:0: —— 
EDITORS’ TABLE. 
EDITORS: A. S. PACKARD, JR., AND E. D: COPE. 
—— There is still a disposition in certain quarters to disparage 
and even to ridicule attempts at the construction of genealogical 
trees. One criticism made is that they are nothing less than sys- 
tems of classification. To this we would reply that of course 
: are. Our systems of classifications are efforts to display 
M à graphic way our conceptions of the affinities of natural groups. 
fir more generalized forms are placed lowest and the more spe- 
cialized higher, and the aberrant forms are placed at a distance from 
the more typical. Some naturalists arrange natural groups in the 
form of constellations; but the greater number, irrespective of any 
theory, Copy, simply for i , the form of a tree with branches 
of unequal sizeand length. Unconsciously every systematic biolo- 
Sist thus constructs a genealogical tree. If now, he be an evolu- 
