48 Mr, H. J. Carter on the 



(which is about 1 \ inch in diameter) being thus not only at 

 some distance from it, but itself presenting no appearance of 

 any kind of nucleus beyond a confused mass of cellular struc- 

 ture (fig. 2,d). 



In all instances, however, this kind of nucleus is connected 

 at some point with the exterior or circumference of the Par- 

 heria (figs. 1, h, and 2, &), although in many specimens dark, 

 apparently isolated spots of the brown substance like " rot " 

 may show themselves in different parts of it (fig. 1, c). 



It is therefore possible that when the Parkeria was in a 

 fresh state and the Millarella in a plastic one the latter might, 

 after having destroyed part of the substance of the former 

 and thus having made room for itself, have drawn in the fora- 

 miniferal detritus of which the white or chalky portion of the 

 nucleus is composed in the fossilized body, if not the origina- 

 ting particles of the glauconite too, seeing that this mineral 

 may commence in the chamber of a foraminiferal test, as I 

 have already explained ('Annals,' I. c. p. 181), although the 

 former, at least, could not have got into it afterwards. 



The nucleus of Parheria, as Prof. Nicholson has lately 

 stated (?. c. p. 9), is probably always some foreign body, such 

 as the " fragment of a shell," and when otherwise it is pro- 

 bably like that of Millarella above described (figs. 1 and 2). 

 Again, when it is the " fragment of a shell," this may be 

 that of a multilocular one, viz. Cephalopodous, wdrich is gene- 

 rally the case, or a flat, turbinated one of a small Gasteropod, 

 which seems to be not so frequent, judging from the small 

 collection of Parkerice in my possession, which does not 

 amount to more than a dozen specimens, although many more 

 than this have passed through my hands ; still, even when 

 the nucleus is a " fragment of a shell," it may be remarked 

 that the Millarella, although present in other parts of the 

 Parkeria, does not emanate from it, but that, on the con- 

 trary, the confines of the " shell-fragment " remain so clearly 

 defined that the commencement of the Parkerian structure 

 (that is, its coenenchyma) may be seen to rest upon it all round, 

 while it is frequently so small that, in this way, the coenen- 

 chymal structure may be traced up to nearly the centre of the 

 specimen. Indeed, although the Parkeria seems to have 

 generally sought some foreign body as a nucleus to begin 

 upon, it is only when the nucleus is a Millarella that it is in 

 connexion with the circumfereince of the organism. On the 

 other hand, the centre of the Parkeria may present no distin- 

 guishable nucleus whatever, and the spot of Millarella be 

 situated at some distance from it towards the circumference, 

 as in the case mentioned, which strongly supports the infer- 



