552 MM. Foord and Crick — On Nautilus elegans, Shy. 



rather a deep sinus on the periphery. The ribs bifurcate, and even 

 trifurcate, in some places on the sides of the shell ; the interspaces 

 dividing them are about one-half the width of the ribs themselves. 

 The ribs mark the cast with very conspicuous plications ; the former 

 become flattened hy weathering, but, where well preserved, they are 

 seen to be distinctly rounded. 



Remarks. — In a letter just received by one of us, Dr. Paul Fischer 

 makes the following interesting observations on the present species, 

 and we gather from his remarks that there is no hope of determining 

 with certainty the specimen selected by d'Orbigny as his type. Dr. 

 Fischer states : " The type of Nautilus pseudoelegans is difficult 

 to recognize. According to the dimensions given in the original 

 diagnosis (diameter 240 millimetres, thickness 160 mm. Paleont. 

 Franc p. 60) our specimens, No. 4834 D, which were sent to you, 

 are typical. 1 Moreover, they come from the neighbourhood of 

 Vandeuvre (Departement de l'Aube), where the species was found. 



" But the drawing given by d'Orbigny is faulty ; first, its dimen- 

 sions do not agree with the description ; then the drawing being 

 reduced to one-third the natural size, the specimen which it repre- 

 sents should have been at least 360mm. in diameter; besides, the 

 ornaments are wanting in the drawing on a great part of the last 

 whorl 



" Consider then the figure by d'Orbigny as only approximate. 

 D'Orbigny has restored a great many of his plates, for which, in my 

 opinion, he is very much to blame 



" In the d'Orbigny collection no specimen is specially marked as 

 the type. But d'Archaic (Hist, du progres de la geologie, vol. iv. 

 p. 295) quotes N. pseudoelegans, and he has given to the Museum 

 a specimen marked type. This specimen is small (greatest diameter 

 150 mm.), and agrees neither with the figure nor with the dimensions 

 given in d'Orbigny's original description. 



" Perhaps the true type was contained in the collection of the 

 geologist, Clement Mullet, who showed d'Orbigny over the locality 

 where N. pseudoelegans abounds?" 



The majority of the British examples of this species which we 

 have seen are very much crushed. There is, however, in the British 

 Museum collection a large natural cast (No. C 1368) which in all 

 probability belongs to this species. It is from the Lower Greensand 

 and measures 1 foot 2 inches in its greatest diameter and about 

 8 inches in width. The septa are rather distant from each other, 

 being about two inches apart on the sides of the shell ; the sutures 

 are slightly flexuous upon the sides and also upon the periphery. 

 The test is not preserved, but the robust form of this specimen and 

 its general appearance ally it to N. pseudoelegans. 



Affinities and Differences. — These will be found detailed on p. 546. 



Horizon and Locality. — Lower Greensand. Maidstone and Sand- 

 gate, Kent. 



1 Two specimens were sent, both numbered 4834 D ; the larger one is represented 

 in Fig. 3. 6 . * 



