122 PROCEEDINGS OF THE NATIONAL MUSEUM vol 77 



thicker and the numerous costae, although only partly developed, 

 are much finer. It is named for Rev. W. Howchin, of Australia. 



POLYMORPHINA FRONDIFORMIS Searles Wood 



Plate 31, figures 10 a, b 



Polymorphina frondiformis Searles Wood, in Morris, Catal. Brit. Fossils, 

 1843, p. 62. — Jones, Parker, and H. B. Brady, Crag. Foram., Pal. 

 Soc, vol. 19, 1866, App. i, ii (footnotes), pi. 1, figs. 62, 63, 69.— H. B. 

 Brady, Parker, and Jones, Trans. Linn. Soc, vol. 27, 1870, p. 241, 

 pi. 41, figs. 33 a-c. — Jones, Foram. Crag., pt. 3, 1896, p. 271, pi. 1, 

 figs. 62, 63; pi. 4, figs. 11-14. 



Test elongate, oval, greatest breadth above the middle, more acute 

 toward the base than the apertural end; chambers elongate, com- 

 pressed, not much embracing, arranged in an entirely biserial series, 

 each succeeding chamber removed much farther from the base; wall 

 rather thick, ornamented with irregular, rough, longitudinal costae, 

 interrupted at the sutures, sometimes almost smooth; sutures but 

 little depressed, not very distinct; aperture radiate. 



Our largest specimen measures, length' 3.40 mm. ; breadth 1.60 mm. ; 

 thickness 0.30 mm. 



Polymorphina frondiformis with generally large dimensions is one 

 of the most specialized and well-defined species of the genus. Its 

 surface ornamentation is not definite, but is usually present to a 

 greater or less extent. It consists of circular or oval beads or of more 

 or less interrupted costae distributed unequally in a longitudinal 

 direction over the flat sides of the test. 



Distribution. — The present species appears to be limited to the Crag 

 in England, in which it is rather common. Searles Wood first reported 

 it from the Crag at Sutton, near Colchester, where our specimens 

 were also obtained. Brady, Parker, and Jones record it from the 

 Coralline Crag of East Anglia. 



GeBus SIGMOMORPHINA Cushmait and Ozawa, 1928 



SIGMOMORPHINA NYSTI (Reuss) 



Plate 32, figures 1 a, b 



Polymorphina regularis Mxjnster var. nysti Reuss, Bull. Acad. Roy. Sci. 

 Belg., ser. 2, vol. 15, 1863, p. 152, pi. 3, fig. 42. 



Test compressed, lanceolate, greatest breadth in the upper half, 

 tapering toward the base, margin angulatej chambers elongated, 

 arranged in an open, clockwise, sigmoid series, each succeeding cham- 

 ber removed much farther from the base; sutures not depressed, 

 almost straight, distinct; wall smooth; aperture radiate. 



Length of figured specimen 1.15 mm.; breadth 0.45 mm.; thick- 

 ness 0.20 mm. 



