ART. 6 FOEAMINIFERA: POLYMORPHINIDAE — CUSHMAN AND OZAWA 51 

 GUTTULINA (SIGMOIDINA) SILVESTEII Cushman and Ozawa, new species 



Plate 37, figures 6, 7 



Test almost circular in outline, much inflated in the central part, 

 periphery more or less angular; chambers elongated, arranged in 

 either clockwise or contraclockwise, quinqueloculine series, involute, 

 extra chamber short, inflated, not extending down to the base; 

 sutures very little depressed, distinct; wall smooth, rather thick; 

 aperture radiate. 



Length 0.60-1.25 mm.; breadth 0.60-1.05 mm.; thickness 0.40- 

 0.65 mm. 



Holotype. — (Cushman Coll. No. 9863.) From the Miocene (Jan- 

 jukian). Filter quarry, Batesford, near Victoria, Australia. 



It differs from Sigmoidina pacifica in its circular test, more angulate 

 peripheries and very slightly depressed sutures. It may be specially 

 noted here that when the present species has an extra chamber the 

 chamber is added in the same series as the arrangement of the earlier 

 ones, although it is much shorter and does not extend down to the 

 base. (See pi. 37, fig. 7a.) From this fact it is easily understood 

 that the species is not a young stage of Sigmoidella elegantissima. 



Guttulina disciformis , reported by Terquem from the Pliocene of 

 the Isle of Rhodes, is very similar to the present species and may 

 represent either a young stage or the megalospheric form of the species, 

 but it has a rounded periphery, and it may be possible that the speci- 

 men is the young of some other species, such as Sigmoidella elegan- 

 tissima, which we found in the Miocene of Pontlevoy, France. There- 

 fore we do not like to place these specimens under such an ambiguous 

 species as G. disciformis. 



The species is named for Prof. A. Silvestri of Milan. 



Distribution. — Recent from Australia, New Zealand and the Philip- 

 pines; fossil in the Miocene of Australia. We have specimens from 

 the following localities : 



Recent. — Australia, Wool Bay, Yorkes Peninsula, west side of St. 

 Vincent Gulf, South Australia; Hardwick Bay, east side of Spencer 

 Gulf; New Zealand, Oamaru, 50 fathoms; off the Big King, 98 fathoms. 



Miocene. — Australia, Janjukian, Filter quarries, Batesford, Victoria. 



Genus PYRULINA d'Orbigny, 1826 



PYRULINA GUTTA d'Orbigny 



Plate 13, figures 1 a-c 



Pyrulina gutta d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 267, No. 28, 

 model 30. — Ozawa, Contr. Cushman Lab. Foram. Res., vol. 5, 1929, 

 p. 39, pi. 6, figs. 4, 5. 



Polymorphina gutta H. B. Brady, Parker, and Jones (not d'Orbigny), 

 Trans. Linn. Soc, vol. 27, 1870, p. 218, pi. 39, figs. 3a, &.— Sherborn 

 and Chapman, Journ. Roy. Micr. Soc, ser. 2, vol. 6, 1886, p. 755, pi. 

 16, fig. 6[?]. 



