Lanius excubitor and Lanius major. 3& 
Though, as yet, we are far from having obtained exhaustive 
observations, it would seem a fact that throughout the Eastern 
Arctic region the inner spot is wholly or in part suppressed 
oftener than is the case in the southern districts. This 
characteristic tendency increases with the distance east; in 
Eastern Asia the transition is probably imperceptible to the 
form which, under the name of L. borealis , we know from 
North America* (an exceptional approximation to this form 
occurs even in Western or Central Europe). In like manner 
does the transition proceed to other forms in which the white 
colour predominates, viz., throughout Southern Europe, 
North Africa, and East Asia. 
Hence we must infer that L. excubitor (like L. ludovi- 
cianus , and other species of the same genus, if in a less 
degree) has a remarkable tendency to variation, more espe¬ 
cially as regards the extent of the white colour on the tail- 
feathers and on the bases of the secondaries, as also in the 
development of the vermiculations across the abdomen. This 
variation occurs in some cases quite individually, in others 
more constantly, a definite kind of variation being exhibited 
with greater and greater frequency according as the distance 
from the region constituting the habitat of the typical 
form increases, till a number of more or less constant 
races, known to us under various names, at length are 
produced. 
To enumerate all these varieties, or “species,” derived 
from L . excubitor , does not come within the object of the 
present paper. In conclusion, I shall merely enumerate such 
of the forms as are found with greatest frequency in the 
tracts of the Palsearctic Region. 
1. The typical form (L. excubitor , forma excubitor ), with 
its fully and normally developed inner spot on the secon¬ 
daries, inhabits chiefly Central and Western Europe, and 
produces normally young which, even in the nesting- plumage, 
exhibit this mark in full development, as in the old birds. 
* “My immature bird from the Amoor is undistinguishable from 
L. borealis, Vieill., but I have seen an almost complete series from it 
to L. excubitor ” (Seebohm, Ibis, 1880, p. 115). 
