AMEKTOAN SPECIES OF ORTHOPHBAGMINA AND LEPIDOCYCLINA. 



41 



chambers in vertical columns, up to 20 or more 

 in a column in the thickest central portion, the 

 individual chambers at least four or five times 

 as wide as high in section. 



Horizontal sections show the rectangular 

 chambers of the equatorial region several times 

 as long as wide, the lateral chambers forming 

 an irregular network about the sections of the 

 pillars, often several columns of vertical cham- 

 bers between the pillars. 



Diameter, 1.5 to 3.5 millimeters. 



Type specimens from U. S. G. S. station 

 3475, Boston mine, near Santiago, Cuba; 

 collected by A. C. Spencer. 



This seems to be a common Cuban species, 

 occurring in material from several stations as 

 follows : 



3448. Limestone from hillside south of Ponupo man- 

 ganese mine, LaMaya, near Santiago; T. W. Vaughan, col- 

 lector. 



6117. Boulder from the band of limestone on hill east 

 of railroad and south of Cristo, near Santiago; C. W. Hayes, 

 collector. 



6118. Limestone near railroad on trail to mines south of 

 Cristo; C. W. Hayes, collector. 



6119. Isabella and Boston manganese mine, near San- 

 tiago; C. W. Hayes, collector. 



6120. Loose material, Santiago Province, exact locality 

 unknown. 



6122. Greensand limestone, Boston manganese mine, 

 3 miles east of Cristo, Santiago Province; A. C. Spencer, 

 collector. 



6123. Resting on ore bed, 4 to 6 feet thick, Ponupo 

 manganese mine, Santiago Province; A. C. Spencer, 

 collector. 



6124. Foraminiferal limestone, Ponupo manganese 

 mine, Ponupo, Santiago Province; R. T. Hill, collector. 



6125. Railroad cut near San Nicolas manganese mine, 

 ■west of San Luis, Santiago Province; C. W. Hayes, col- 

 lector. 



7666. Sierra Guaso, northeast of Guantanamo; N. H. 

 Barton, collector, 1916. 



The embryonic chambers of this species so 

 far as seen are unequal in size and very com- 

 parable to those seen in the subgenus Nephro- 

 lepidina of Lepidocydina, the larger one kidney 

 shaped and partly embracing the smaller. 



In its general characters this species sug- 

 gests 0. douvillei Schlumberger, but it differs in 

 several essential details. 



Specimens of what is apparently the megalo- 

 spheric form of this species are abundant in 

 material from the Pilar mine, Oriente Province, 

 Cuba; E. F. Burchard, collector. Some of 

 these are figured in Plate VII, figure 1. 



Orthophragmina minima Cushman. 



Plate VII, figure 3. 



Orthophragmina minima Cushman, U. S. Nat. Mus. Bull. 

 103, p. 97, pi. 41, fig. 1, 1918. 



Test circular, very small, slightly more than 

 2 millimeters in diameter; thickness somewhat 

 less than half the diameter; central portion 

 very strongly umbonate, nearly rounded to a 

 point about two-thirds of the distance from 

 the center to the periphery; from this point to 

 the periphery the surface is nearly flat ; surface 

 of the test comparatively smooth. 



The horizontal section through the equa- 

 torial chambers shows very fine hexagonal 

 chambers and the embryonic chambers nearly 

 equal in size. 



Plate VII, figure 3, shows weU the contour 

 of the test in vertical section, the strongly 

 curved central lunbonate portion making up 

 two-thirds or more of the width, and the 

 peripheral flange with its nearly parallel sides. 

 The chambers are very small except the embry- 

 onic central chambers, which are nearly equal 

 and have a straight division line between. The 

 lateral chambers are in vertical coliunns, but 

 the test is without pillars. In the central 

 region there may be more than 20 chambers in 

 a vertical column, and even on the peripheral 

 flange there are usually three or four chambers 

 in a column on each side of the equatorial 

 chambers. 



Type specimen from U. S. G. S. station 6512, 

 in the big white limestone from the river bed 

 above the ice plant near David, Panama; 

 D. F. MacDonald, collector. 



This is a very small species, yet it has an 

 abundance of very fine chambers. There is 

 an exceptional development of lateral cham- 

 bers in the region of the periphery. 



Orthophragmina clarki Cushman, n. sp. 



Plate VII, figures 4, 5. 



Test circular, much compressed; central 

 portion somewhat raised and slightly umbonate; 

 surf ace finely granular or papillate; thepapillae 

 of the central umbonate region largest and most 

 conspicuous, but others scattered over the 

 remainder of the surface except at the extreme 

 periphery, where they are lacking; slope of the 

 test very gradual from umbo to periphery. 



Equatorial chambers typical of the genus^ 

 elongate, rectangular, those of the outer annuli 



