TYPE SPECIMENS OF PALEOZOIC FOSSILS 265 



obolella Billings 



Obolella crassa Hall 



1617 T8 1 50 hypotype Orbicula? crassa Hall. Paleontology 



of New York. 1847. 1 : 290. 



Obolella crassa Hall & Clarke. Paleontology ot 

 New York. 1892. v. 8, pt 1, pi. 2, fig. 34. 



Lower Cambric Troy N. Y. 



S. W. Ford purchase. 



1618 T8 o 50 hypotype Ford. American journal of science. 1881. 



3d ser. 21 : 131, fig. 1. 



Walcott. United States geological survey bulletin 30. 

 1886. pi. io, fig. if. 



Walcott. 10th annual report of the director of the 

 United States geological survey. 1890. pi. 71, fig. 4L 



Hall & Clarke. Paleontology of New York. 1892. 

 v. 8, pt i, pi. 2, fig. 35. 



Lower Cambric Troy N. Y. 



S. W. Ford purchase 



1619 78 8 ff ° hypotype Ford. American journal of science. 1881. 



3d ser. 21 : 131, fig. 2. 



Walcott. United States geological survey bulletin 30. 

 1886. pi. 10, fig. id. 



Walcott. 10th annual report of the director of the 

 United States geological survey. 1890. pi. 71, fig. 4d. 



Hall & Clarke. Paleontology of New York. 1892 

 v. 8, pt 1, pi. 2, fig. 36. 



Lower Cambric Troy N. Y. 



S. W. Ford purchase 



1620 *Af£ hypotype Walcott. United States geological survey 



bulletin 30. 1886. pi. 10, fig. 1. 



Walcott. 10th annual report of the director of the 

 United States geological survey. 1890. pi. 71, fig. 4. 



Lower Cambric Troy N. Y. 



S. W. Ford purchase 



1C21 •~ £ . r ' i! HYPOTYPE (combination figure) Walcott. United States 



geological survey bulletin 30. 1S86. pi. 10, fig, il>. 



Walcott. 10th annual report of the director of the 

 United States geological survey. 1S90. pi. 67, fig, 1. 



1 1 -. 1 I ambric Troy N. Y. 



s. w. Ford purchase 



Obolella desiderata $€4 l'.lkania desiderata 



