678 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



internode are the same, and both have the characteristic black joints. 

 The zooecia of franciscana are slightly larger and are usually more 

 expanded toward the distal end. 



The ovicell is more inflated than in geniculata and the ooeciostome 

 is situated on the frontal border with its tube curved backward. 



Reported by Robertson from Orca, Alaska, to southern California at 

 numerous places, and by O'Donoghue from British Columbia. It is 

 one of the most common crisias along the California coast from low 

 tide to 25 fms. Okada also found it common in Japanese waters. 



Hancock Stations: Numerous stations about the islands and along 

 the coast of southern California from San Francisco southward to San 

 Diego; Dillon Beach, north of San Francisco (R. J. Menzies) ; Mussel 

 Point, northern California (A. E. Blagg) > San Juan Islands, Puget 

 Sound (J. L. Mohr) ; much more abundant than C. geniculata, often 

 occurring in considerable masses on piles and floats ; low tide to 50 fms. 



Genus GRISIA Lamouroux, 1812 



Genotype, Sertularia eburnea Linnaeus, 1758 :810. In this well-known 

 genus the internodes are longer, with 5 to as many as 30 or more zooecia 

 in some of the species. These are arranged very symmetrically in two 

 alternating series, the short projecting peristomes giving the edges a 

 serrated appearance. The ovicells or gonozoids are usually in the mid- 

 line of the frontal surface, between the rows of zooecia. It is unfor- 

 tunate that the ovicells, which are often lacking, are necessary for the 

 positive determination of most of the species. Dr. Alice Robertson gave 

 an excellent account (1910:229-245) of the Pacific coast species known 

 to her and her key is used here, with additions and slight modifications. 



The little shrub-like colonies of the crisias are often abundant in 

 shallow water, attached to anything that may afford a lodging place 

 and conspicuous because of their chalky whiteness. 



Key TO THE Species of Crista 



1. Ooeciostome with a cap-like flap extending forward above 



the aperture operculata 



Aperture of ooeciostome without covering flap 2 



2. Ovicell very short and wide, ooeciostome almost wanting, pore 



round ; internodes long and slender elongata 



Ovicell elongate and gradually expanding 3 



