NO. 1 OSBURN: EASTERN PACIFIC BRYOZOA — CHEILOSTOMATA 145 



half of the frontal length, oval, the descending cryptocyst well developed ; 

 the rim is elevated, with a large oval scutum which has an alcicorn deco- 

 ration and is flared upward at the distal end. There are one or two strong 

 spines at the outer angle and usually a smaller one at the inner corner. 

 The marginal avicularia, on all of the zooecia, are large and conspicu- 

 ous; the frontal ones small and wanting on most of the zooecia. The 

 vibracula are small and inconspicuous, wedge-shaped, transverse, set just 

 above the avicularian chamber, the groove transverse and the rather 

 stout flagellum shorter than the zooecial length ; they are rare and may 

 often be wanting from a whole internode. 



Ooecia subglobose, somewhat flattened on the front, a smooth tri- 

 angular area above the aperture from which fine lines radiate. 



Miss Robertson's record (1900:318) from Kodiak, Alaska, was later 

 (1905:256) referred to Tricellaria (Alenipea) erecta (Robertson). In 

 the following record the specimen conforms closely to Atlantic specimens, 

 except for the scarcity of the frontal avicularia. 



Alitak Bay, Alaska, 30 fms, U. S. Alaska Crab Investigation, Sta- 

 tion 100-40. 



Scrupocellaria scabra van paenulata Norman, 1903 

 Plate 18, fig. 6 

 Scrupocellaria scabra var. paenulata, Nordgaard, 1918:32. 

 Scrupocellaria scabra var. paenulata, Osburn, 1932:11. 



This high northern variety agrees with the typical form in most re- 

 spects, but it is somewhat larger in all measurements and the scutum is 

 greatly expanded, flared upward at its tip and extends forward above 

 the proximal border of the ovicell. It appears to replace the typical form 

 in high northern waters ; it is the common variety about Greenland and 

 the American Archipelago. 



Point Barrow, Alaska, G. E. MacGinitie, collector, Arctic Research 

 Laboratory, abundant. 



Scrupocellaria scruposa (Linnaeus), 1758 

 Plates 19, fig. 1, and 21, fig. 2 

 Sertularia scruposa Linnaeus, 1758 :815. 

 Scrupocellaria scruposa, Hincks, 1880:45. 

 Scrupocellaria scruposa, Hastings, 1930:703. 



A rather stout species, the internodes of three or four zooecia in a 

 series, the joint crossing the outer zooecia immediately proximal to the 

 opesia. 



