OF FOSSIL MULTILOCULAR SHELLS. 419 



The new genus Endosiphonites differs from goniatites and nautilus in 

 the position of the siphuncle, and it agrees with both in the direction 

 of the strise of growth. The whorls, though contiguous, never envelope ; 

 and the septa seem usually very nearly simple. Taking DOrbignys 

 classification, which being founded chiefly on the position of the siphun- 

 cle, must be preferred, we i-efer this genus to the family Nautilacea, 

 and place it between Nautilus and Lituite. 



We come now to consider the species, and the English localities 

 not having been searched with a view to the discovery of these fossils, 

 we have at present only three sufficiently well defined to admit of de- 

 scription. These are figured in Plate VIII. and I have named them as 

 follows : — 



(1). Endosiplionites Mirnsteri noh. Plate VIII., Fig. 1. This being 

 the largest species, I have named it in honour of the first discoverer 

 of the genus. The individual figured is an extremely beautiful fossil, 

 and, as will be seen from the figure, shows the siphuncle very clearly. 

 It is partially burnt, having been obtained by the fracture of a lump 

 which had passed through a kiln without being reduced to a calx ; 

 so that most of the strife of growth are destroyed, although I have 

 no doubt they were before the burning sufficiently clear. It is the 

 only species in which there are decided lobes, and is remarkable for 

 the very large size of the last whorl, the area of the aperture being 

 more than five times as large as that of the corresponding chamber 

 in the former whorl. It is also very flat, the length of the aperture 

 being more than twice its width, and this without any appearance of 

 the shell having been injured or crushed. It measures four inches across. 



(2). E. carinntus nob. Plate VIII., Fig. 2. This species is re- 

 markable for its elliptical form, and for having a keel running along 

 the dorsal margin. Its dimensions are fourteen-tenths by nine-tenths of an 

 inch. It is marked by a series of fine but beautifully distinct strite, 

 which may be clearly seen in some parts of the specimen figured, where 

 in all probability the original shell remains. This is the species alluded 

 to above as having a very large siphuncle, seen in the figure at (a). 

 Vol. VI. Paut III. SH 



