(i) 28 PaLrontologia Sinica Ser. A 



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Lophospira gerardi Grabau (sp. nov.) 

 Plate III, Fig. 7. 



Shell of less than medium size, with an apical angle of Go to 70 degrees. Whorls 

 embracing to a point about midway between the two carinse, exposing the lower portion 

 of the whorl for an amount equal to about half the shoulder width. Shoulder flat to very 

 gently concave, with a well-marked peripheral carina, bordered above and below by a 

 distinct spiral line. The upper of these spiral lines is separated from the median carina 

 by a distance about twice that between the carina and the lower bordering spiral, produ- 

 cing the appearance of a peripheral band on the margin of the shoulder. Shoulder angle 

 about 95. Lower carination generally well marked, its distance from the periphery 

 being somewhat less than the width of the shoulder. The space between the two 

 carinations is gently concave or nearly flat, while below the lower carina, the whorl 

 slopes rather abruptly to the umbilical region. Aperture subquadrate; umbilicus not 

 observed. 



Lophospira gerardi has many of the characters of L. perangulata Hall, from the 

 Stones River and Lowville-Black River groups, of the central United States, New York, 

 and Canada, the chief differences being the greater apical angle of our species. In the 

 American form the final whorl is also often laxly coiled, and the peripheral carina is 

 trilineate. 



HORIZON AND LOCALITY : This species and its variety were found by the Survey 

 expedition in the Machiakou or Actinoceras limestone of the Chaokouchuang region in 

 the Kaiping coal basin. The specific name is given in honor of M. Jaques Gerard, 

 geologist and engineer of the Chaokouchuang mines of the Kailan Mining Admin- 

 istration. 



Lophospira gerardi 

 variety laxa Grabau (var. nov.) 

 Plate III, Fig. 8. 



This is a gerontic mutation of L. gerardi. The early whorls are slightly more 

 embracing than in the normal form, making a greater apical angle (nearly 80 degrees), 

 but the later whorls become slightly separated, producing a lax-coiling adult. This 

 results in a pronounced sutural channel, bounded without by the sharp upper angle of the 



