var tamed Swartu, Marsh Wrens of California. al? 
size, so is not to be looked upon as indicative of mere intergradation 
with the smaller and darker race paludicola. There are, however, 
a number of small sized individuals in the series, which, despite 
this character, are readily distinguishable from the latter race. 
These are nearly all from the Colorado and Mohave deserts. 
In Oberholser’s description (Auk, Vol. 14, 1897, pp. 186-196) of 
Cistothorus palustris plesius mention is made (p. 192) of an August 
specimen from Fort Klamath, Oregon, which though referred to 
plesius, is regarded as intermediate between that race and paludi- 
cola. This skin is before me, and the characteristics mentioned 
are readily appreciable. There is another specimen at hand, a 
January bird, from Camp Harney, in the same general region, 
which is even darker in appearance, though again apparently 
referable to plesius. The Fort Klamath bird can be closely 
matched as to color by others from southern California, which I 
also regard as non-typical examples of plesius. 
The question arises as to the relationships of the breeding bird 
of south-central Oregon to estuarinus of the Suisun region, a ques- 
tion that cannot be settled without material from the Sacramento 
Valley. This region is not represented by a single specimen in 
the series under consideration. It is at any rate a possibility that 
estuarinus extends north through the Sacramento Valley to south- 
ern Oregon, its range interposed between those of plesius and palu- 
dicola, and that at the north mergence of characters occurs with 
either one or both of the latter races. The few birds at hand from 
southern Oregon, and from certain other points (as noted under 
estuarinus) are certainly suggestive of such a possibility. 
