NO. 5 fraser: hydroids 181 



times, to Dr. Allan Hancock, as Director of the Allan Hancock Founda- 

 tion, to Dr. Irene McCulloch, who has done so much to get the hydroid 

 collection together, and to other members of the Foundation staff, who 

 have contributed to the venture. I am under continued obligation to the 

 University of British Columbia for providing accommodation and the 

 necessary facilities for carrying on such research. Happily, this introduc- 

 tion provides a good opportunity to recognize and acknowledge all such 

 obligations. 



Distribution 



Of the 274 species in this latest collection, 50 are described as new, 

 and in 4 other species, the gonosome has been described for the first 

 time. Since the collection has covered little new ground, it seems to be 

 more useful to make some general observations on the whole Eastern 

 Pacific Hancock collection rather than to confine them to this recent 

 collection. 



To consider in detail the distribution data of each of the 274 species 

 would be a big task in itself, and the results obtained would be quite 

 outside the scope of this paper. In a paper on Distribution and Relation- 

 ship in American Hydroids^ just published by the University of Toronto 

 Press, 29 families, 108 genera, and 685 species of American hydroids were 

 written up comparatively as to distribution and relationship, and an at- 

 tempt at correlation between these was made when such was possible. 

 These 1,500 additional records change the situation very materially, 

 especially in the region between Point Conception and Cape San Lucas. 

 If these additional records are considered in detail, the results should be 

 presented as an addendum to the distribution volume, but should be asso- 

 ciated with the five papers on the Hancock hydroids of the Eastern 

 Pacific and the single paper on the Caribbean hydroids. 



In considering the distribution of all of the 344 species of Hancock 

 hydroids from the Eastern Pacific, it seems advisable to present a distri- 

 bution table in which, because of the great increase of distribution records, 

 it is possible to divide the Eastern Pacific into smaller sections, 11 of 

 them, to give a more detailed picture of the whole distribution. These sec- 

 tions are: the oceanic islands (OC), Peru, Ecuador (Ec), Colombia 

 (Col), Panama (Pan), Central America (CA), Mexico (Mex), Gulf 

 of California (G of C), west coast of Lower California (WLC), south- 

 ern California, extending from the southern boundary to Point Concep- 

 tion (SC), and the remainder of the northeast Pacific (NEP). A 

 twelfth column is added to show the species that are found as well in the 

 northwestern Atlantic (NWA). 



