﻿I 6 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 47 



slight development or total absence of the laminated secondary de- 

 posit, and the presence of cystiphragms in both the axial and periph- 

 eral regions, are the principal diagnostic characters of Monticulipora 

 as now understood by us. ( >ur reasons for distinguishing the new 

 generic group Orbignyella will be found under the discussion of that 

 genus. 



Through the kindness of Dr. M. Boule of the Museum d'Histoire 

 Naturelle, Paris, we have recently procured a fragment of the speci- 

 men upon which D'Orbigny based his description of Monticulipora 

 mammulata, the first of the four species and the accepted type of the 

 genus Monticulipora established by him at the same time. The frag- 

 ment received from Dr. Boule was carefully sectioned, and the inter- 

 nal characters of the species drawn by Mr. Bassler. The reproduc- 

 tions of these drawings on plate vi, 1-3, though adding nothing 

 to the present knowledge, nevertheless serve to fix the status of the 

 genus and species. They show further that Ulrich's interpretation 

 of the species in 1882 1 was correct and that the synonymy given then 

 by that author and later by Nickles and Bassler 2 is also correct. 



The principal features of the genus are the peculiar granulose 

 wall structure and the presence of cystiphragms in both axial and 

 peripheral regions. The range of variation in mode of growth and 

 mature form of the zoarium, from incrusting sheets to irregular or 

 globular masses, and from frondescent to quite regularly ramose 

 forms, as exhibited in the species referred to the genus by Ulrich, 

 is still considered as properly embraced within the limits of a single 

 genus. 



The following species are characteristic middle Richmond forms, 

 the first being the only ramose Monticulipora known to occur in the 

 ( incinnatian group. 



MONTICULIPORA CLEAVELANDI James 

 ( Plate VI. 4-6) 



Monticulipora (Heterotrypa .') cleavelandi James. Paleontologist, No. 6, 



1882, ]). 4). pi. 1. 7. 

 Monticulipora cleavelandi James and James, Jour. Cincinnati Soc. Nat. 



Hist., xi. 1888, p. 15. pi. i, 4. 

 Monticulipora cleavelandi J. F. James. Jour. Cincinnati Soc. Nat. Hist., 



xvin, 1895, P- 68- 



Zoarium irregularly subramose to ramose; branches subcylindrical 



<>r flattened, often 10 mm. or more in diameter. Surface smooth, 



'Jour. Cincinnati Soc. Nat. Hist., v. [882, p. 234. 

 2 Bull. U. S. Geol. Surv., Xo. 173, 1900, p. 324. 



