NO. 1 OSBURN : EASTERN PACIFIC BRYOZOA CHEILOSTOMATA 123 



The name catalinensis may be retained as a nominal variety to include 

 the forms with a more highly branched scutum, which appears to be more 

 constant in warmer waters. The larger scutes are dominant in southern 

 California, but occur less frequently north of Point Conception. 



Tricellaria ternata (Solander), 1786 

 Plate 14, figs. 1 and 2 



Menipea ternataj}ri.\ncks, 1882:3. 



Menipea ternata, Robertson, 1900:316; 1905:251. 



Menipea ternata, O'Donoghue, 1923 :1 7 ; 1926:42. 



Erect and more or less spreading colonies, usually less than 25 mm 

 in height. The internodes, especially near the base of the colony, consist 

 of 3 zooecia, but farther out on the branches there are often as many as 

 5 or 7 ; the joints cross the narrow bases of both outer and inner zooecia 

 at some distance proximal to the opesia. 



The zooecia measure about 0.40 mm in length; they are slender and 

 much narrowed proximally ; the opesia occupies usually less than half of 

 the frontal length ; the scutum varies from a mere spine to a curved 

 spatulate form, which may end in 2 or 3 points ; the stalk of the scutum 

 is attached well above the middle of the opesia and curves slightly down- 

 ward ; spines are 2 or 3 outer and 1 or 2 inner, sometimes quite elongate. 

 Frontal avicularia usually present only on the axial zooccium below a 

 bifurcation, small, and slightly elevated. The lateral avicularia are much 

 larger, present on nearly all of the zooecia. 



The ovicells are globose, prominent, smooth and without pores. 



This is an abundant species in the cooler waters on both sides of the 

 North Atlantic (from southern New England northward to the Arctic 

 region), and has been listed on the Pacific coast from British Columbia 

 southward to Lands End, California, by Hincks, Robertson and O'Dono- 

 ghue. 



Hancock Station 1283-41, South Point, Santa Rosa Island, Cali- 

 fornia, 23 to 28 fms, is the most southerly record. It does not appear to 

 be a common species along the California coast but occurs rather regu- 

 larly from Oregon northward to southern Alaska. 



