80 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



of the operculum, one of these often smaller or wanting ; a pointed spine 

 curving somewhat over the opesia at about its middle, very inconstant, 

 usually some on the zoarium but occasionally wanting entirely. Lateral 

 avicularia are present on one or both sides, mounted on an elevated base 

 close to and distal to the stout spine, often wanting on one side; the 

 triangular mandible directed proximally and somewhat vertically and 

 outward. 



The ovicell is large and prominent; the ectooecial layer forming a 

 ridge across the middle, varying greatly in the amount of calcification 

 and in the form and amount of curvature. The median avicularium is 

 greatly increased in size, with a long-triangular mandible which is turned 

 somewhat sideways; the avicularian chamber united with the ectooecial 

 layer to a greater or less extent, sometimes surmounting the ovicell and 

 seeming to arise from it. 



I am unable to distinguish cassidata O'Donoghue from armifera by 

 any constant character after direct comparison with colonies of the latter 

 from the Atlantic coast. O'Donoghue says of the lateral avicularia, "the 

 mandible lies almost vertically and is directed anteriorly and slightly in- 

 ward," which must be a lapsus calami as his figure (pi. 2, fig. 15) clearly 

 shows it directed proximally and outward. There is considerable varia- 

 tion in size and elevation and in the erection of the mandible, but in all 

 cases they are turned backward and outward as in armifera. 



Hincks described M. armifera from the Gulf of St. Lawrence; and 

 Osburn listed it under M. arctica from Cape Cod, Massachusetts, and it 

 has been reported from the arctic seas of Europe and America. O'Dono- 

 ghue listed cassidata from numerous localities in British Columbia, "a 

 fairly common species and a very characteristic one." 



Hancock Station 1245, Gull Island ofif Santa Cruz, California; oflf 

 San Pedro, California; Nash Harbor, Nunivak Island, Alaska, and Pun- 

 uk Island, Bering Sea. Also common at Point Barrow, Alaska, G. E. 

 MacGinitie, collector, Arctic Research Laboratory. 



Tegella magnipora new species 

 Plate 9, figs. 3 and 4 



Zoarium encrusting, reddish brown in color. Zooecia moderately 

 large, varying in length from 0.65 to 0.90 mm and in width from 0.35 

 to 0.45 mm ; mural rim thin and smooth or slightly granulated ; gymno- 

 cyst moderately developed, sometimes almost wanting ; descending crypto- 

 cyst granulated, narrow, occasionally a little expanded laterally at the 

 proximal corners. The opesia occupy nearly all of the frontal area, ellipti- 



