Report on Organic Remains. 277 



(«) Gyrosi. Those with simple septa. Ex. N. jjompilius. 



(b) Frondosi. With irregular septa, presenting a leafy 

 aspect, and thought more particularly to resemble the crisped 

 leaves of the common parsley. 



The first division comprises by far the greater number of 

 species. To the second division we refer the specimen under 

 consideration, and as we find nothing similar to it in the 

 works to which we have had, access, it may be designated as 



A. Jii]ijp£t£refis, . "* ' * ' " * 



Simplegades ? De Montfort Conchy Holy gie systematique. 



Externally smooth, with slight transverse elevations, which 

 in the smaller whirls are very distinct ; each whirl envelopes 

 one half of the internal contiguous whirl, and thus gives to 

 the septum a peculiar lunated appearance. This is sup- 

 posed to be the last chamber, and a considerable promi- 

 nence on each side near the outer lip, may be considered 

 as analogous to corresponding parts in the Nautilus, where 

 the lips fold round in order to be connected with the sides. 

 The septum irregular, with tubercles on its surface, which 

 towards its junction, with the sides of the shell, assume a 

 branched appearance, similar to the divisions of the Baculite. 

 The outline of the septum, as may be seen by reference to the 

 figure, is semilunated, with the horns produced and somewhat 

 approximated. Thickness one inch. Conjectured diameter 

 of the whole shell two inches. 



Cabinet of the Lyceum. 



pi. v. fig. % $• 



No. 2. Impression of one of the rugose internal whirls of 

 the same species, from the same locality. 

 Cabinet of the Lyceum. 



Vol. II. 35 



