506 NEW YORK STxVTE MUSEUM 



Cycloceras ? (Spyroceras ?) rectiannulatum Hall 



Orthoceras rectiannulatum Hall. Pal. N. Y. 1847. i -.34, pL 



7, fig. 2, 2a 



This species, which is stated by its author to occur in the gray 

 crystalline central portions of the limestone at Chazy, Clinton co.^ 

 is based upon a single specimen. The latter though recorded in the 

 original description as being in the Hall collection has not been lo- 

 cated. Nor have we observed any other specimens with the char- 

 cicters of this species. From Spyroceras subarcuatum it 

 would, according to the description and figure, differ in its straight 

 conch and more distant annulations. Its surface is unknown anct 

 hence a conclusive reference to any of the genera of the Cyclocera- 

 tidae or Kionoceratidae impossible. 



(Cyrtoceras) beekmanense Whitfield 



Cyrtoceras beekmanensis Whitfield. Am. Mus. Nat. Hist.. 



Bui. 1889. 2:57, pi. 10, fig. 2, 3 



This species is based upon a fragment too incomplete for a deter- 

 mination of its position in Hyatt's system of the Cephalopoda and 

 no additional niaterial has been secured. The original description is r 



Shell of moderate size, nearly straight, the arcuation being not 

 more than l^ of an inch in a length of three inches, or one twenty 

 fourth of the length ; tube laterally compressed, giving a very slightly 

 oval section, the lateral diameter being somewhat less than the dorso- 

 ventral. Septa numerous, seven chambers occur within the space 

 of half an inch on the side of the tube near the upper end of the 

 septate portion, not greatly arcuated and of but shallow depth, rather 

 strongly advanced on the inner side of the tube. Siphon unknown. 

 Outer chamber quite long. Surface of the shell apparently smooth. 



It is reported as coming from the crystalline limestone layer of 

 the Beekmantown below the lower Ophileta bed, at Beekman- 

 town (D). 



The form can be distinguished from the few other cyrtoceraconic 

 species of the Beekmantown by its shallow chambers with the ex- 

 ception of Cyrtoceras kirbyi, which, however, is more 

 strongly arcuate and compressed. 



(Cyrtoceras) confertissimum Whitfield 



Plate 38, figure 1-4 



Cyrtoceras confertissimum Whitfield. Am. Mus. Nat. Hist_ 

 Bui. 1886. V. I, no. 8, p. 327, pi. 27. figs. 7-9 , 



A single specimen of this small form was obtained in Aq of the I 

 Fort Cassin beds at Valcour. This we have used to ascertain the 



