4 HISTORICAL SUMMARY. 



principle of seizing what appeared to be the most characteristic variety, and distinguishing it 

 by the specific name, whilst they designate the rest by the addition of Greek letters. In this 

 manner they differentiated no fewer than twelve varieties of Nautilus {Cristellaria) calcar, five 

 of Nautilus {Calcarina) Spengleri, five oi Nautilus {Cristellaria) cassis, five oi Nautilus {Nummulina) 

 lenticularis, three of Nautilus {PeneropHs) planatus. and two of several other species. Still they 

 were so far trammelled by the notion of the Cephalopodous character of these Polythalamia, 

 that they did not advance nearly as far in this direction as there now seems good reason for 

 doing. It was their great merit, however, to have recognised the difficulty which presents 

 itself whenever large numbers of these forms are brought together, instead of evading it by 

 selecting their specific types, and then putting aside, as of no account, all which do not con- 

 form to them, after the manner of certain other systematists. The species described in the 

 work of Fichtel and Moll have been critically studied with their usual care, and their 

 present appellations given, by Messrs. Parker and Rupert Jones (lxxviii). 



At the same period, Lamarck was engaged in the study of the fossil Foraminifera which 

 are so abundantly found in the Calcaire Grassier and other Eocene beds of France, especially 

 in the neighbourhood of Paris. These he described and figured, for the most part, as Cepha- 

 lopods, but in some instances as Corals, in his series of Memoirs on the Invertebi-ated Animals 

 found in a fossil state in the vicinity of Paris (LViii); and he subsequently repeated these descrip- 

 tions and figures in his contribution (lix) to the ' Tableau Encyclopedique et Methodique,' with 

 others derived from the works of preceding authors, and especially from that of MM. Fichtel 

 and Moll. In the original edition of his great systematic treatise on Invertebrate animals (lx), 

 Lamarck repeated his specific descriptions of the foregoing types, with some slight additions, 

 and he distributed them under generic assemblages, many of which he then first introduced. 

 Although these new genera were created under a total misapprehension of the true nature of 

 the group, and were by no means satisfactorily defined, yet many of them (such as Nodosaria, 

 Cristellaria, Botalia, Nummulites, Polystomella, Orbitolifes, and Orbiculina) were truly natural, 

 and have been retained in all subsequent classifications. The species enumerated by Lamarck 

 have been critically examined and identified by Messrs. Parker and Rupert Jones (lxxix). 



A very different appreciation of the value of characters was shown by Denys de Montfort, 

 who introduced into his systematic and illustrated treatise on Conchology (lxvii) descrip- 

 tions and figures of several of the minute shells now ranked as Foraminifera, stating in his 

 introduction that he was far from pretending to have given all their genera, but that he 

 aimed at making some, at least, of their singular forms known to naturalists. To this end he 

 selected several of the types figured and described by Soldani and by Fichtel and Moll, and 

 added others from his own collection, distributing the whole according to his own notions. 

 His delineations of them, however, are of the rudest and most inaccurate character, and his 

 descriptions are no less erroneous, whilst his systematic arrangement displays the worst form of 

 the worst school of naturalists, — varieties being erected, not only into species, but even into 

 genera, upon the slenderest possible basis of difference, and without the least regard to the con- 

 stancy of the characters assumed for their definition. And thus it has come to pass that out of 

 about sixty new generic names introduced by De Montfort, only a single one, PeneropHs, has 

 been adopted by subsequent writers, until I found reason to accept another, Tinoporus, as 

 having been recognised by him as a distinct generic type, though he entirely misapprehended 

 its nature. The forms described by De Montfort have been identified and referred to their 

 proper synonyms by Messrs. Parker and Rupert Jones (lxxx). 



