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



don Clay, whence the " opaque brown " specimen submitted by 

 Boys to Montagu was probably derived. D'Orbigny has recog- 

 nized Montagu's figured specimen as a variety of his Dentalina 

 communis (Tabl. Ceph., Aim. d. Sc. Nat. vii. p. 254, no. 35), which 

 is the same as Lamarck's N. dentalina. 



(D.h.) Suppl.pl. 19.f.5,p. 86. " Nautilus spinulosis." A frag- 

 ment of a pretty spinose Dentaline Nodosaria, very common in 

 the London Clay. It passes, on one hand, losing its ornament, 

 into N. dentalina ; and, on the other, by means of finely costate 

 forms, into N. Rapkanits, the prickles being equivalent to un- 

 developed riblets, and often passing into regular costas. D'Or- 

 bigny has re-named this variety Dentalina Adolphina, in his 

 Toram. Bassin Vienne ;' and D. jloscula, D'Orb., Nod. hispida, 

 D'Orb., and Nod. aculeata, D'Orb., are like varieties. The D. 

 spinescens of Beuss is the same. 



(D. i.) Supplem. pi. 19. f. 6, p. 82. " Nautilus Legumen." This 

 is the recent Nodosaria {Vaginulina^ Legumen, Linn. sp. 



(D. j.) Suppl. pi. 30. f. 9, p. 87. " Nautilus linearis." A de- 

 licate Yaginuline modification of Nodosaria, intermediate between 

 Vaginulina Legumen, Linn., and V. Badenensis, D'Orb. Mon- 

 tagu obtained his specimen from " the shell-bank near Dunbar, 

 North Britain ;" Prof. Williamson has received this shell from 

 other British localities. A fragment from the Norwegian coast 

 is figured in our paper, Annals N. H. 1857, vol. xix. pi. 11. fig. 2. 



(E. a.) P. 191, and Supplem. pi. 18. f. 1, p. 78. " Nautilus 

 umbilicatulus." Montagu refers to Walker's fig. 69 for this 

 shell ; but Walker's two aspects of the specimen show an un- 

 symmetrical shell, like a Truncatulina*. In Montagu's further 

 description in the " Supplement," he describes specimens col- 

 lected by himself from a Sabella ("in the Bay of Kingsbridge"); 

 and his figure differs materially from AYalker's, and represents a 

 small variety of Nonionina asterisans, Fichtel and Moll, sp. It 

 cannot be the Polystomclla-\ striatopunctata, F. & M. sp., which 

 Prof. Williamson has called P. umbilicatula (Monograph, p. 42), 



* See above, p. 339. 



t In the Ann. X. II. ] 857, xix. p. 288, we referred this P. striatopunctata 

 to Nonionina ; but, in spite of its extreme similarity of form to the small 

 Nonionina, we now adhere to Mr. Williamson's opinion of its being a 

 Polystomella. We must, however, go further, and regard it as specifically 

 the same as P. crispa. 



We may here observe that the tribe of small Nonionina; converging 

 round N. asterisans, although conveniently considered as a subspecific 

 group, yet in reality are essentially of the same specific type as that to 

 which Polystomella crispa belongs. They may be said to be arrested or 

 feebly developed conditions of the form in which a luxuriant growth of 

 exogenous shell-matter symmetrically bridges over the septal sulci and the 

 aperture, and otherwise thickens and ornaments the shell. 



