26 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 89 



A description of the Mexican specimens identified by me as L. 

 tournoueri is as follows : 



Test small, lenticular, usually bordered by a narrow rim. Surface 

 ornamentation variable, in most specimens a few strong papillae 

 produced by the emergent distal ends of the pillars form an apical 

 crown, in others the pillars are so reduced in size as to be scarcely 

 noticeable. The surface of the test is generally strongly reticulate. 

 The megalospheric form has a diameter of 2 to 4 mm and a thickness 

 of I to 1.5 mm. 



The embryonic chambers are of nephrolepidine type, a larger 

 chamber partly embracing a somewhat smaller one. Chamber walls 

 relatively thick. The width of the two chambers in an equatorial plane 

 is 0.29 mm. The smaller chamber has a length of 0.19 mm, a width of 

 0.14 mm ; the length of the larger chamber is 0.32 mm. The height of 

 the larger chamber in a vertical section is 0.22 mm. The surrounding 

 wall is 22 ix in thickness. 



The equatorial layer has a thickness at the center of about 80 /x, 

 at the periphery, about 135 /x, the measurements including both walls. 

 The equatorial chambers have a radial diameter of about 52 [x, and a 

 transverse diameter of about 50 fi, at the center of the test. They 

 increase in size toward the periphery where their radial diameter is 

 6y fx, and the transverse diameter 52 fi. In plan the equatorial chambers 

 vary from short-spatulate at the center to hexagonal and slightly 

 elongate-hexagonal at the periphery. 



There are on each side of the equatorial layer about 10 lateral 

 chambers, arranged in regular tiers, at the center. They decrease in 

 number outward until there is but a single layer at the periphery. 

 Directly over the embryonic apparatus the lateral chambers have a 

 length of about 90 /x and a height of about 30 /x ; at the periphery in 

 the same tier their length is 225 /x and their height, 45 fx. Pillars are 

 rather strong, 75 /x to 112 fx in diameter, irregularly spaced in the 

 central area of the test. 



Locality and geologic horizon. — -Near Tampico, Arbol Grande, 

 Tamaulipas, Mexico, collected by D. R. Senimes. The geologic horizon 

 is Oligocene, whether middle or upper is not certain, but upper appears 

 more probable. 



LEPIDOCYCLINA (NEPHROLEPIDINA) TEMPANII Vaughan and Cole, n. sp. 



Plate 13, figs. 3-6 



Test small, lenticular, usually with a slight rim. Surface papillate,, 

 the degree of papillation variable, papillae much better developed on 



