UNIVERSITY OF CALIFORNIA PUBLICATIONS 
ZOOLOGY 
Vol. 2, No. 5, pp. 235-322, Pls. 4-16 December 9, 1905 
CONTRIBUTIONS FROM THE LABORATORY 
OF THE 
MARINE BIOLOGICAL ASSOCIATION OF SAN DIEGO. 
Ve 
NON-INCRUSTING CHILOSTOMATOUS 
BRYOZOA OF THE WEST COAST 
OF NORTH AMERICA. 
BY 
ALICE ROBERTSON. 
The bryozoa of the west coast of North America constitute 
a fauna practically unknown to science. From time to time 
during the last half century some scattering work has been done, 
the earliest being by Trask (757), who deseribed and figured a 
number of species from San Francisco Bay. Later Gabb and 
Horn (’62), in connection with their work on the Geological 
Survey of California, identified a number of species of bryozoa, 
both recent and fossil; and Hincks (’82 and ’84) reported on 
a large collection from Queen Charlotte Islands. Still later, the 
present writer (’00) reported on the bryozoa of the Harriman 
Alaska Expedition, having previously published on the Ento- 
procts of San Francisco Bay (’99). Besides the work of these 
investigators, mention should be made of that of Conrad (755) 
and of Fewkes (’89), both of whom added to our knowledge of 
the bryozoa of this coast. 
The following pages constitute the first of a contemplated 
series of papers on the bryozoa of the Pacific coast of North 
America, and include about half of the sub-order Chilostomata, 
comprising, in the main, those Chilostomes which grow as free, 
flexible colonies. The inclusion of the adherent genera Aetea 
