124 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



Tricellaria gracilis (Smitt), 1867 

 Plate 14, figs. 3 and 4 

 Menipeaternata,mncks,\SS4:3. i^U : Cnbi^^n , l^ 



Menipeaternata ffracilis, Robertson, 1900:317. ^^ 



Menipea gracilis, Robertson, 1905 : 253. 

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



Zoarium more diffuse than in ternata, with longer internodes. Zooecia 

 often very elongate, occasionally as much as 1 mm, though within the 

 same colony there may be internodes with zooecia not more than 0.40 

 to 0.50 mm in length, in any case the length is due chiefly to the exten- 

 sion of the preopesial region. The opesia is elliptical, its rim slightly 

 raised and the cryptocyst well developed. The scutum varies greatly, 

 from a mere curved spine to broadly spatulate, and often it is wanting; 

 the same is true of the spines, two, one or none on the outer angle and 

 one or none on the inner corner. Small lateral avicularia are quite con- 

 stant, but the frontal ones occur only rarely near the end of an internode. 

 The ovicell is subglobose, not so much elongated as in M. ternata, the 

 surface lightly striated longitudinally. 



The difference between gracilis and ternata, which have often been 

 confused, are as follows in the Pacific coast specimens: in gracilis the 

 zooecia are much more elongate and less robust; the internodes are longer 

 with a larger number of zooecia, though ternata is not limited to three ; 

 the lateral avicularia are noticeably smaller, and the ovicell is somewhat 

 shorter and slightly striated. They do not seem to intergrade, though 

 admittedly they are closely related. 



Hincks' record of M. ternata for "Cumshewa Harbor," British Co- 

 lumbia, is for the "form with many cells in an internode," and in the 

 synonymy he gives "Menipea gracilis." Robertson separates gracilis and 

 records it from Prince William Sound. O'Donoghue also considers it 

 distinct and records it from several localities in British Columbia waters. 



Off Hallo Bay, Alaska, 28-40 fms. Station 139-40, and Icy Straits, 

 east end of Pleasant Island, 32-35 fms. Station C.5-41, U. S. Alaska 

 Crab Investigation. 



Tricellaria pribilofi (Robertson), 1905 

 Menipea pribilofi Robertson, 1905 :257. 

 Menipea pribilofi, O'Donoghue, 1923 :18. 



Internodes consisting of 3 zooecia except the ooecial internodes which 

 usually consist of 5 ; joints dark colored. Zooecia relatively short and 

 stout, broad at the top, attenuated below, aperture occupying less than 



