Ilydractiiiia, Piirkeria, antf Stroinatojx.ra. 4.'> 



Influenced, liowcvcr, hy tlic [)re.sence f»f the. " iiriinonlial 

 clianiber-conc " figured by Dr. Carpenter in pi. 72, cl-c4, and 

 j)l. 73, fig. 2, //, 1 wa.s induced to observe, in the short " Note on 

 /*(//-/.v'r/(7," added to my paper on the Polijtrcindta (Ann. 6i 

 Mag. Nat. Hist. 187(5, vol. .wii. p. 208), tliat it could be 

 hardly doubted that rarki'ria wa.s a species of Fcjraininifera, 

 but that " one of the chief charactens of the Foraniinifera," 

 viz. the " foraniinated area? of which the so-called 'nuniniu- 

 line tubulation ' is an example," had not been demonstrated. 

 The ciiief object, however, of this " Note " was to state that 

 the fibre of which Parl-en'a was coni])osed was not *' arena- 

 ceous," and that the structure of Parl,cri<i was not identical 

 witli the " labyrinthic structure" of the foraminiferal test 

 Lituola nautiloiJea^ Lam., var. canarieiisis^ D'Orb. 



Up to this time I was under the impression that Parkeria 

 had been a species of Foraniinifera ; for I liad only one sjieci- 

 men myself, in which I could see all that had been described 

 by Dr. Carjjenter excej)ting the " primordial chamber-cone." 

 Subsequently, however, I began to doubt the Foraminiferal 

 nature of Parkeria ; and, the nucleus of my specimen in shaj)e 

 presenting exteriorly the pointed end of a Belemnite, which 

 extended from one side of the sphere to the other, I began to 

 think that it had been a sponge which had grow^n round the 

 end of a l^elemnite. But what sponge? was the next ques- 

 tion. Lttjf'an'a seemed to be the only genus that in fibro- 

 reticulated horny structure, when fossilized, would come near 

 to that of Parkeria ; and so for some time I, from the 

 presence of this great foreign nucleus, abandoned the P^'orami- 

 niferal for the Spongial view, still not heartily, till June 

 last, when, my friend ]\Ir. W. J. SoUas having given me 

 some more specimens of Parkeria obtained from the Upper 

 Grecnsand of Cambridge, amongst which was an entirely 

 w/iinfiltrated central portion about -, V i"ch in diameter that, on 

 fracturing the circumferential or hard infiltrated part when 

 the specimen was entire, had fallen like a nut out of its 

 shell, I abandoned both these viewsj' as will be seen hereafter. 

 This nuclear portion also had been so broken as to expose the 

 centre, on one side of which is a small circular or ellipsoidal 

 cavity that appears to have originally contained tiie object 

 on which the organism had commenced its growth (PI. \'^ill. 

 fig. 13, c). 



Seeing, then, that Prt;7iT;va grew upon a foreign body which 

 was on one side of the centre, 1 also felt satisfied that no 

 Foraminiferous test, cither recent or fossil, with which I was 

 acquainted, presented either the fibro-reticulated structure of 

 Parkeria or possessed a foreign body for a point d^appui to 



