476 Messrs. W. K. Parker and T. R. Jones on the 



D'Orbigny, and others, we have here appropriated them on the 

 plan which we shall hereafter explain. 



The idea that seems to have been present in Linnseus's mind 

 when grouping these little Polythalamous shells had reference 

 to the diminution of the coiled condition of form in passing 

 from the Nautiloid Cristellaria Calcar to the moniliform and 

 rod-like Nodosaria Radicula and iV. Fascia. In this arrange- 

 ment the relative position of the specific forms has seldom more 

 than a distant relation to their typical value. We therefore do not 

 bind ourselves to the acceptance of the first named of an allied 

 group, as indicative of the typical value of such specific forms. 

 Thus, in the Nodosarian forms, Nos. 281-288, which belong to 

 one type- species, we do not choose either Nodosaria Radicula 

 (the simplest) or Nod, Raphanistrum (the most perfect form), 

 but A^. Raphanus, which, among those that Linnseus catalogued, 

 is the best as a well-developed model of Nodosarian growth, 

 combining all the essential characters of the group, — the other 

 Linnsean names being retained for the several varieties, to be 

 used for the purpose of reference if occasion requires. 



For a similar reason, we do not accept as a type-name for the 

 species either Planorbulina rugosa (No. 277) or Peneroplis urn- 

 bilicatus (No. 278), these being well adapted for the varieties 

 for which they were respectively intended, whilst the type-forms 

 of the species to which they belong will severally retain the 

 names of PL far eta and P. planatus given to them by others. 



In Mr. S. Hanley's ' Ipsa Linnsei Conchylia' (1855) are re- 

 marks on the " Nautili" of the ' Syst. Nat.,' as determined from 

 Linnets manuscripts and Collection. These notices, though 

 avowedly less elaborate than the remarks on the mollusks in the 

 same volume, are very valuable, and bear witness to the author's 

 acumen and conscientious care. In the new edition of Wood's 

 ' Catalogue of Shells' (1856), Mr. Hanley has also removed 

 many difficulties in the study of the Foraminifera figured in the 

 works of the older naturalists, by most carefully tracing out 

 " the pictorial synonymy" of the several species there illustrated, 

 as far as the limits imposed by the character of the work per- 

 mitted. We have to express our personal obligation to Mr. 

 Hanley for favouring us with much assistance in our study of 

 the Linnsean species. 



(A.) Linne's Nautilm Calcar (1162. 274), being a well-de- 

 veloped symmetrical form, is a good type of the Cristellaria. 

 From this lenticular form we have divergent modifications, some 

 of which affect the globular, others the discoidal and the crozier- 

 like forms. The last of these are generally known as Marginu- 



