NO. 5 FORAMINIFERAL GENERA — LOEBLICH AND TAPPAN 29 



Cushman, 1940, p. 204). Other treatises do not mention the genus at 

 all (Colom, 1946; Glaessner, 1948, Pokorny, 1954). 



It remained for Wood (1949, p. 245) to call attention again to the 

 unique character of this species. He mentioned that "each of the 

 elliptical spicules which form its test is a single crystal of calcite. . . 

 Each crystal lies with its c-axis parallel to the length of the spicule. 

 It seems extremely probable that these spicules are a direct secretion 

 of the protoplasm, they appear to be usually larger in the larger speci- 

 mens, and nothing identical in form is known in any other animal." 

 He also suggested the interesting hypothesis that because of its com- 

 pletely distinctive wall character Carterina is undoubtedly a recent 

 offshoot and "might in the future give rise to a whole galaxy of new 

 types," perhaps eventually as distinctive as the Porcellanea. 



A feature of Carterina which has apparently escaped the observation 

 of all workers is the subdivision of the chambers by secondary septa. 

 This is not usually apparent from the dorsal exterior (fig. loa), but 

 when the specimen is dampened, the septa can be very easily seen 

 through the thin wall (figs, 9a,b) and their development can be deter- 

 mined. On young free specimens the secondary septa are visible ex- 

 ternally on the ventral side (fig. lob). The earliest chambers are not 

 subdivided, then only two or three subdivisions occur per chamber, 

 and the early secondary septa consist of slight projections from the 

 outer wall. With progressive growth the later chambers have more 

 numerous partitions, up to as many as 15 per chamber, and the parti- 

 tions are nearly complete, extending nearly or completely across the 

 chambers. These subdivisions can be easily distinguished dorsally from 

 the regular septa, as the true septa are oblique, the chambers crescentic, 

 and the secondary partitions perpendicular to the peripheral wall. 



As far as is known this genus is monotypic. Only one species other 

 than the type species has been referred to Carterina, C. fnlva Cushman 

 (1924, p. 10) and Cushman and Wickenden (1929, p. 5), but the 

 latter is a Trochmnmina-like form and agglutinated, not formed of 

 calcareous spicules secreted by the organism itself, and thus completely 

 different from Carterina. 



REFERENCES 

 Bermudez, p. J. 



1952. Estudio sistematico de los Foraminiferos Rotaliformes. Estados 

 Unidos de Venezuela Bol. de Geol., vol. 2, pp. 7-230, pis. 1-35. 

 Brady, H. B. 



1881. Notes on some of the reticularian Rhizopoda of the Challenger Expe- 

 dition; Pt. 3. Quart. Journ. Micr. Sci. London, n. s., vol. 21, 

 pp. 31-71. 



