434 Mr. T. Davidson on LamarcVs species of 



my sincere thanks to those gentlemen of the Garden of Plants 

 for the great confidence they reposed in me, and for the unlimited 

 assistance they have always shown to those who take an interest 

 in the study of science. 



All the species described were not however to be found in the 

 collection of the Garden of Plants ; the greater number belonged 

 to Lamarck's private collection, which became at his death the 

 property of the Prince Massena, who sold them to M. le Baron 

 Benjamin Delessert, and which now form part of his extensive 

 and celebrated museum. M. Chenu, Curator of that Museum, 

 in the most liberal manner placed at my disposal the remaining 

 type specimens of Lamarck's collection. The specimens from 

 the Garden of Plants are all ticketed by M. Valenciennes, the ori- 

 ginal describer; all those in B. Delessert' s collection are labeled 

 by Lamarck himself. M. Valenciennes has also, in the kindest 

 possible manner, given me all the information in his power rela- 

 tive to some of the species which had presented any difficulty. 



The original monograph of Fossil Terebratulse, published thirty 

 years ago (1819), was one of the first works written by the justly 

 celebrated Valenciennes, and appeared at a time when little was 

 known on the subject, and it is but justice that those species 

 then established should be retained in the nomenclature where 

 no objections exist. At that period authors were not in the 

 habit, or rather did not feel so much the importance, of giving 

 any reference to locality or strata ; they simply contented them- 

 selves with a short Latin description of the outer form of the 

 object under examination, so that with very few exceptions there 

 exist no positive data as to the locality or geological position of 

 the specimens in Lamarck's work. There is also some difficulty 

 in a few cases of defining which were Lamarck's real types, as 

 several specimens of different species are sometimes placed on 

 one tablet, the description of which is adapted to more than one 

 form ; and lastly, it is possible that some of the specimens now 

 in B. Delessert' s hands may have been displaced while in the 

 possession of Prince Massena. I have however compared as care- 

 fully as possible the specimens with the descriptions, and by the 

 kind assistance of M. Valenciennes (where doubts existed) am 

 able to lay before the public the figures of each species drawn 

 from the types on which they were established. I must however 

 add, that in some few cases the specimens belonging to Lamarck's 

 collection were in bad condition, which I have restored in the 

 figures from well-preserved specimens of the identical species in 

 my own collection, in order to prevent misconceptions as to the 

 shells intended as types. I have also thought it advisable in the 

 text and in the plates to preserve the same order and numbers as 

 used in Lamarck's sixth volume (1819) j and in order to keep 



