NO. 10 AMERICAN SPECIES OF LEPIDOCYCLINA VAUGHAN 23 



Cushman's figure of the embryonic chambers of a specimen identi- 

 fied by him as L. morgani should be compared with his figures ( 1920, 

 pi. 33, figs. 4-9) of the embryonic chambers of L. yurnagunensis. The 

 similarity is obvious. The embryonic chambers of L. yurtiagunensis 

 vary from Lepidocyclina s.s. to Nephrolepidina, and some are almost 

 Pliolepidina, as Cushman has shown. The embryonic and the equa- 

 torial chambers of L. yurnagunensis yar. morganopsis are similar to 

 those of typical L. yurnagunensis, from which the variety differs 

 solely by its more greatly developed pillars, which terminate in 

 pustules on the surface. 



Cotypes. — Locality no. 7543, two thin sections and a few uncut 

 specimens, U.S. National Museum. 



LEPIDOCYCLINA HODGENSIS Vaughan and Cole, n. sp. 



Plate 12, figs. 1-5 



Test somewhat compressed lenticular to robustly lenticular, usually 

 bordered by a narrow rim, outline generally irregularly subcircular. 

 Diameter varies from 2.2 to 3.5 mm, thickness from i to 2 mm. 

 Surface papillate, the degree of papillation variable. In some speci- 

 mens very pronounced papillae are developed in the apical region, 

 the remainder of the test being covered with much finer papillae. In 

 other specimens the entire test is covered with fine papillae. On some 

 specimens there are ill-defined radiating costae, which are more 

 conspicuous on the narrow rim and cause in most cases the polygonal 

 outline of the test. Pits occur between the pillars ; the entire effect is 

 to give the surface of the test a very rugose appearance. 



The following description of the internal features is based on 

 sections of microspheric individuals ; the megalospheric form was not 

 discovered in any of the preparations that were made. 



The embryonic apparatus of a microspheric individual is composed 

 of about 2 whorls with a diameter of 100 /t. The outer whorl has 6 

 chambers. The equatorial chambers vary from those with curved 

 outer and converging inner walls with pointed or slightly truncated 

 inner ends to those of short-spatulate form. They increase gradually 

 in size from the center to the periphery. Those at the center have a 

 radial diameter of 20 ju, ; a transverse diameter of 35 /x ; those at the 

 periphery have a radial diameter of about 45 /x, a transverse diameter 

 of 35 fx. Plate 12, figure 5 shows a section, X 85, which indicates the 

 form and size of both the embryonic apparatus and the equatorial 

 chambers. 



The lateral chambers are very numerous and are arranged in regular 

 tiers between the rather large pillars. Over the center of the test 



