54 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
POLYMORPHINA p’Orz. 
P. ovata v’Ors. 
P. ovata D’ORB., 1846, Bass. tert. Vienne, p. 233, Pl. XIII. Figs. 1-3. 
P. ovatu Br., 1884, Chall. Rep., 1X. p. 564, Pl. LX XII. Figs. 7, 8. 
The typical ovata of d’Orbigny has in its arrangement of the segments some- 
thing in common with the compressa of the same author; but the ovata of Brady 
differs from both in having the last two segments somewhat larger than in the 
type. At any rate Brady’s representation of this form perfectly agrees with our 
only specimen from the Pacific. 
Pacific. 885 fathoms ; rare. 
CRISTELLARIA Lamarck. 
C. rotulata Luck. 
Lenticulites rotulata LMcx. (1804), 1830, Encycl. Méth. Vers., Pl. 466, Fig. 5. 
Nodosarina calear Gors, 1882, Ret. Rhizop. Caribb. Sea, Sv. Vet. Ak. Hdl., XTX. 4, 
p. 49, Pl. IIL. Figs. 57-59 (cultrata), 60, 61 (monstrous). 
C. rotulata Br., 1884, Chall. Rep., IX. p. 347, Pl. LXIX. Fig. 13. 
C. rotulata Goks, 1898, Arct. & Scand. Foramf., Sv. Vet. Ak. Hdl., XXV. 9, p. 59, 
Pl. X. Figs. 559-578. 
This species attains a high development in the tropical seas, where it affects 
depths of 200-1500 fathoms. Specimens from the Pacific have some tendency 
to sutural limbation, and the keel of the margin is often somewhat thickened. 
Such forms may be referred to Robul. ornata D’ORB., but it is impossible to as- 
sign to such fickle features any specific importance. Between the forma culirata 
Mrrrv. and the type no definite boundary line can be traced. 
Pacific. 660-1201 fathoms. 
Caribbean Sea. 68-1600 fathoms. 
ALLIED Forms: — 
1. C. calcar Liv. 
Nautilus calcar Lin. (partly), 1758, Syst. Nature, ed. X. p. 709. 
Nodosarina caicar Gos (partly), 1882, Ret. Rhizop. Caribb. Sea, Sv. Vet. 
Ak. Hdl., XTX. 4, Pl. III. Figs. 54-56. 
Cristellaria calcar Br., 1884, Chall. Rep., p. 551, Pl. LXX. Figs. 9-15. 
The rowelled form of the type is not so common as this itself, although 
in the Caribbean Sea it is pretty often met with. The form with deeply 
serrated marginal wing is an intermediate form between cultrata and calcar. 
Caribbean Sea. 25-420 fathoms. 
