No. 13.— Some Hgdroids from Puget Sound. 
By Gary N. Calkins. 
With six plates. 
In 1876 Professor Clarke remarked on the scarcity of hydroids 
found on the west coast as compared with the east coast from 
Maine to New York, the ratio being nearly five to one in favor 
of the latter, although the eastern coast line from Maine to New 
York is but two thirds as long as the western. The twenty-four 
species which Clarke then described were collected along the coast 
from San Diego, California, to Vancouver Island, B. C., and did 
not include the forty Alaskan species which he described later 
in the same year. “It should be borne in mind however,” says 
Clarke (’76a, p. 251), “that most of the collecting on the Pacific 
coast has been done along the shore, the dredge having been little 
used, and there is little doubt that when the fauna has been more 
thoroughly investigated the number of hydroids may be at least 
doubled. Such a variety as exists on the New England coast can 
hardly be expected from our Pacific shores south of Vancouver 
Island, for the waters there do not afford the same diversity in 
temperature.” In addition to the difference in temperature must 
be noted the topographical differences in the two regions. The 
rocky, precipitous coast of the west shore with its great depths is 
very different from the long stretches of shallow water characteristic 
of the eastern coast. It will be observed, however, that the west 
coast hydroids have never been so extensively studied as those of 
the east coast, a few scattered localities only having been examined, 
and there is reason to believe that, when more points on the coast 
are searched, the number of hydroids will be found to be not only 
doubled but multiplied many times. When the Alaskan hydroids 
are more carefully investigated, the number of west coast species 
will be still more increased, for here the topographical conditions 
are less severe and, in the region about Sitka at least, the water is 
much more shallow and considerably warmer than farther south in 
«/ 
the region of Vancouver, Washington, and Oregon. The collec¬ 
tion of Sitka hydroids made during the summer of 1897 by the 
Columbia University zoological expedition was much more extensive 
than that made in Puget Sound, but the material, descriptions, and 
