216 



1« 



The theca is quite thick; on the outer surfaces are shghtly projecting costae. These 

 are broad and dotted with several rows of small granulations. There is no epithecum. 



There are 24 septa in 3 ordines and 3 cycles. Six in the first ordo are larger than the 

 others, but as far down the calyx as may be seen they do not form columella. 



Cutting crosswise reveals a lamella-like columella, formed by the elongation of a 

 single septum. This proves the species to belong to the genus Sphenotrochus. The upper 

 septal edge is smooth and projects slightly beyond the edge of the calyx. The lateral surfaces 

 of the septum are practically smooth. Many dissepiments are seen in the interseptal com- 

 partments and the upper part of the coral is readily distinguished from the lower. 



Locality: Danien: Coral chalk at Faxe. 



4. Sphenotrochus latus, v. Koenen. 



Sphenotrochus latus 1885 v. Koenen: Ueber eine paleocäne Fauna von Kopenhagen. Göt- 

 tingen. S. 106. Tab. V. Fig. 12 a, b, c. 



This species belongs in certain cases to those fossils which give the chalk its special 

 character. Wherever it is found it occurs in great numbers. In small loose blocks from 

 Ystad and Halsted I have seen it in enormous quantities. 



I have nothing further to add to v. Koenen's description. 



Locality: Younger Danien. Copenhagen harbor; Vestre Gasværk. 



5. Ceratotrochus ambiguus, Forchhammer and Steenstrup. 



Table III. Figs. 1 b, 5 and G. 



This species belongs to those commonly found in the coral chalk from Faxe. It appears 

 as stone kernels, but there are a few remains of impressions which permit a description of 

 its external appearance. The stone kernel is obovate-conical in form, gradually pointed toward 

 the base of the coral. The axis is sometimes straight, but as a rule bent either once or in the 

 form of an S. 



The coral may attain a length of 35 mm with a diameter at the edge of the calyx 

 varying between 12 — 18 mm. 



The stone kernel shows traces of 50 — 60 septa in 6 ordines containing 1 incomplete 

 and 7 complete cycles. The septa from the second and in part from the third ordo as well, 

 are large and well-developed, whereas the interjacent septa are small. The interseptal com- 

 partments of the stone kernels, then, are grouped in 4's. The single groups are separated 

 by deep furrows thus rendering the stone kernels easily recognizable. A calycinal cross-cut 

 shows that the calyx is quite deep. A cut further down reveals loosely united inner septal 

 edges. There was no true columella and there were no dissepiments, for the stone kernel 

 extended without break to the base of the coral. 



The lateral .surfaces of the septum were covered with rows of such small granulations 

 as to appear practically smooth. 



