230 MESSRS. BRADY, PARKER, AND JONES 
fications as they occur. Many of them may be associated with external conditions, such 
as climate, depth of water, and the like; and some of the peculiar forms, the result of 
gradual alteration, afford evidence of a certain value in respect to geological age. 
Distribution.—The range of Polymorphina regularis is nearly identical with that of P. 
anceps. The Middle and Lower Tertiaries of Germany, and the Crag of Antwerp, are the 
only localities in which its occurrence is noted. 
POLYMORPHINA COMPLANATA, D'Orbigny. (Plate XL. figs. 14, a, b; Woodcuts Fj.) 
? Polymorphina lingua, Roemer, 1838, Neues Jahrb. fiir Min., Jahrg. 1838, p. 385, pl. 3. fig. 25. 
? P. obscura, id. ibid. p. 385, pl. 3. fig. 23. 
? P. campanulata, id. ibid. p. 385, pl. 3. fig. 22. 
? P. teretiuscula, id. ibid. p. 385, pl. 3. fig. 24. 
lingua, Philippi, 1844, Beitráge zur Kenntniss d. restes, nord-west. Deutsch. pp. 41, 69; 
Reuss, 1855, Sitzungsb. k. Akad. Wissensch. vol. xviii. p. 248, pl. 7. fig. 77. 
complanata, D'Orbigny, 1846, For. Foss. Vien. p. 234, pl. 13. figs. 25-30. 
Philippii, Reuss, Sitzs. Ak. Wissen. vol. xviii. p. 248, pl. 7. fig. 76. 
subrhombica, Reuss, 1861, ibid. vol. xliv. p. 239, pl. 7. fig. 3. 
obscura, Reuss, 1864, ibid. vol. 1. p. 471, pl. 7. figs. 8-10. 
complanata, Karrer, 1864, Sitzungsb. k. Akad. Wissensch. vol. 1. p. 716 (table) ; Jones, Parker, end 
Brady, 1866, Monogr. Crag Foram. pl. 1. figs. 52, 53, 60. 
T 
VTT 
Characters.—Shell much compressed, elongate or subrhomboidal. Chambers elongate, 
oblique, arranged in two regularly alternating series. Septal lines but slightly excavated. 
Surface smooth. Aperture radiate. Length jj inch or more. 
The figures given by M. D'Orbigny in the * Vienna-Basin ” monograph, to represent 
his Polymorphina complanata, indicate very wide and thin specimens, with an almost 
angular or rhomboidal lateral aspect. Such specimens may be regarded as the extreme 
examples of a considerable series which have as a common character the regular alter- 
nating or Textularian arrangement of their chambers. They vary amongst themselves 
in certain particulars—to a certain extent in the degree of compression of the shell, but 
far more in its relative length and width. The Tdh outlines are copied from some 
of the figures included in the list of synonyms. 
f j 
P. lingua, P. complanata, F. DOrbigns P. subrhombica, 
after Reuss. from the Crag. after D'Orbign after Reuss. 
We see no reason why the Proroporus Schultzei of Prof. Reuss should not be regarded 
as the extreme form of the series, at the opposite end to the short outspread variety which 
originally received the name now adopted for the whole. Its shell is thin and flat, and 
the arrangement of its segments distinctly Textularian ; its anomalous length alone dis- 
