Nomenclature of the Foraminifera. 17 



the Fourth Fasciculus the Systematic Table of the Distribution 

 of these Cephalopods, indicating, by numbers corresponding to 

 those of the Models, the names of the specimens sent, and the 

 order of their classification." 



With the Fourth Fasciculus the following note was issued : — 

 " The coloured Models represent the fossil shells ; the white 

 Models, the recent shells. The place and shape of the siphuncles 

 are indicated by the marks or black spots. " 



In his Introduction to M. D'Orbigny's memoir in the same 

 volume of the ' Annales des Sciences Naturelles,' p. 99, M. Fe- 

 russac says that two of the Fasciculi of Models had been pub- 

 lished, and that the other two would soon follow. The Models 

 therefore were issued, partly, before November 7th, 1825, when 

 the Memoir was presented to the Academy of Sciences ; and 

 though we do not know the exact date of the publication of the 

 third and fourth sets, we shall here regard them as belonging 

 to about the same period (1825-26). 



M. D'Orbigny's researches on Foraminifera appear to have 

 arisen from his father's attention having been directed to these 

 Microzoa; for the elder D'Orbigny, who was a physician at 

 Esnaudes, near Rochelle, wrote to M. Fleurian de Bellevue, in 

 1819, on his discovering, on the shores of the Atlantic, micro- 

 scopic Cephalopods, among which he had seen " living Lenti- 

 culines, Rotalies, Discorbes, Spirolines, &c." (See Annales de 

 Physique, vol. xxxviii. p. 187.) The younger D'Orbigny en- 

 larged his knowledge of these little shells by the collection of 

 numerous samples of sea-sand and of fossiliferous deposits from 

 various parts of the world, working perseveringly and methodi- 

 cally for several years, reducing already published notices and 

 his own observations to a system, which, though artificial 

 throughout and otherwise defective, was very useful ; he described 

 the general characters and external features with care, illus- 

 trating his descriptions by the Models now under consideration 

 and the elaborate plates of his noble quarto and folio volumes 

 on the Foraminifera, and leaving in the end an extensive collec- 

 tion of material. His several works and their numerous illus- 

 trations, chiefly relating to the larger specimens which had come 

 under his notice, are necessarily the groundwork for writers on 

 Foraminifera up to the present time. 



We will now proceed to the examination of the Models 

 seriatim, in the order in which they were originally numbered 

 by D'Orbigny. A series of carefully prepared outlines appended 

 to this paper (Plates I., II., & III.) will assist in forming a cor- 

 rect appreciation of our remarks. In these plates the forms 

 represented by the Models are grouped, as far as may be, ac- 

 cording to their respective families: — the Miliolida {Vertebra- 

 Ann. $ Mag. N. Hist. Ser.3. Vol.xvi. 2 



