32 THE NAUTILUS. 



170. "Same as 89." 

 172. Murex babylonius. 



Plate 156 was represented only by a blank, but numbered, 

 page in this copy when received. Through the courtesy of 

 Mr. C. W. Johnson, I have been able to supply the omission 

 by an admirable water-color copy of the plate in the copy 

 owned by the Boston Society of Natural History. 



The written index, while of course of no scientific value, is 

 of interest both as showing the changes that had been adopted 

 in current nomenclature between the date of the engraved 

 index and that of the written one and as affording an, at least, 

 approximate date when the present copy was put together 

 and bound. 



In the nomenclature of the species represented on the 160 

 plates covered by the engraved index, there are no less than 89 

 changes in generic and 87 in specific names in the written 

 index. The accepted nomenclature of the written index is 

 apparently that Gmelin, whose Systerna Natura was published 

 in 1788-1792. Thus the two species illustrated on plate 67 are 

 given in the engraved index as Limax nucleus and L. faba. 

 The former is now known as Cassidula nucleus (Martyn) and 

 the latter as Partula faba (Martyn). In the written index 

 both are referred to "Helix'". According to Pilsbry (Man. 

 Con., XX, p. 236) Gmelin was the first to designate the latter 

 as ''Helix faba" in 1791, and according to Kuster (Con. Cab., 

 Auriculacea, 1841, p. 29) he also referred nucleus to the same 

 genus. 



Everything in the make-up of this copy seems to indicate 

 that it must have been one of the latest copies issued and was 

 made up of such plates as were then on hand. The entire 

 omission of plate 156 would seem to show that there were no 

 copies left of that plate. The numeration, part written, part 

 engraved, and some both written and engraved; the lack of 

 uniformity in the matter of the neat-lines and the addition 

 of twelve plates not included in the original work, all point 

 in the same direction. 



In the written index under plate 67 (Cypraa aurantium) 

 is appended the following note: "N. B. See Ency. Brit., v. 9, 



