36 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
C. cylindrica KarrER, 1877, Hochquell. Wasserleit., Abh. geol. Reichsanst. Oesterr., 
IX. p. 373, Pl. XVI. Fig. 4. 
Gois, 1882, Ret. Rhizop. Caribb. Sea, Sv. Vet. Ak. Hdl., XIX. 4, p. 62, Pl. IV. 
Figs. 77-81. 
Brapy, 1884, Chall. Rep., IX. p. 896, Pl. XLVIII. Figs. 32-88. 
C. rudis Goes, 1894, Arct. & Scand. Foramf., Sv. Vet. Ak. Hdl., XXV. 9, p. 48, 
Pl. VIL. Figs. 408-412. 
This form together with C. Soldanii is a very prominent constituent of the 
bottoms in certain localities of the Caribbean Sea, though sparsely represented 
in the collections of the ‘** Albatross.” 
It is very variable in size, smoothness, and shape, from slender cylindric to 
broad ovoid. 
Caribbean Sea. 150-300 fathoms ; not rare (Goés). 
C. communis p’Ors. 
Plate IV, Figs. 9-15. 
C. communis D’OrB. (1826), 1846, Bass. tert. Vienne, p. 196, Pl. XII. Figs. 1, 2. 
Text. gibbosa f. bigenerina Gos, 1882, Ret. Rhizop. Caribb. Sea, Sv. Vet. Ak. Hdl., 
XIX. 4, p. 79, Pl. V. Figs. 162-164; forma levigata, pygmy, smooth, with the 
larval stage reduced, sometimes biserial, aperture often porous. 
C. communis Br., 1884, Chall. Rep., IX. p. 394, Pl. XLVIII. Figs. 1-13. 
C. communis Gos, 1893, Arct. & Scand. Foramf., Sv. Vet. Ak. Hdl., XXV.9, p. 20, 
Pl. VII. Figs. 856, 867 (forma levigata). 
C. communis occurs in two forms, one slender and smoother, and a stouter 
one. The former, Plate IV. Figs. 9-15, seems to belong only to the Caribbean 
Sea, the latter is common to both seas; the larval stage is in the former very 
reduced and short, as the whole colony is usually of smaller size, the surface 
white and nearly smooth, the shell agglutinated of fine calcareous matter. 
Pacific. 772-1471 fathoms, large form; at 1100 fathoms plentiful. 
Caribbean Sea. 25-1830 fathoms; forma levigata 300 fathoms (Goés). 
ALLIED Form :— 
C. eoceena GimpeL. Plate IV. Figs. 16-25. 
C. eocena GiimBEL, 1868, For. Nordalp. Eocan, K. Bayr. Ak. Wis. Abhdl., 
X. 2, p. 601, Pl. I. Fig. 2. 
Valvulina triangularis v. eocena Gos, 1882, Ret. Rhizop. Caribb. Sea, Sv. Vet. 
Ak. Hdl., XIX. 4, p. 88, Pl. XI. Figs. 401-403. 
C. communis f. eocena Gos, 1893, Arct. & Scand. Foramf., Sv. Vet. Akad. 
Hdl., XXV. 9, p. 41, Pl. VIIL Figs. 368-377. 
Thicker and of coarser sand construction than the type. It has often a 
tendency to labyrinthic structure; the form is sometimes cylindric, but 
often the test widens with age, assuming a conical shape. 
Caribbean Sea. 68-1830 fathoms. Not common. 
