74 MB. H. WOODS ON THE MOLLTJSCA [Feb. l8g6, 



Order Ammonoidea. 

 Family Lytoceratidse, Neumayr. 

 Genus Ptychoceras, d'Orbigny, 1 1840. 

 Ptychoceras Smithi, sp. nov. (PI. II. figs. 1, 2.) 



Description. — Shell circular in section, ornamented with simple- 

 continuous ribs, which become oblique where the shell is recurved. 

 Suture-line imperfectly known ; siphonal lobe large ; siphonali 

 saddle broad, bifid. 



Affinities. — Ptychoceras gaultinus of Pictet ('Moll. Poss. des 

 Gres Verts des Envir. de Geneve,' 1847, p. 139, pi. xv. f. 5, 6) is 

 near to this species, but differs in that the ribs suddenly become- 

 much more prominent and distant where the shell is recurved. 



Remarks. — The type of this species is in the Woodwardian 

 Museum ; it is named in memory of the late Montagu Smith. 



Distribution. — Chalk Eock of Cuckhamsley, and Winchester. 



Genus Hamites, Parkinson, 1811. 



A fragment of a shell, apparently belonging to this genus, is in 

 the Montagu Smith collection from Cuckhamsley ; it has a length of 

 21 millim., and is provided with ten broad ribs, but is not sufficiently 

 perfect for specific determination. 



Genus Heteroceras, d'Orbigny, 2 1850. 

 Heteroceras Betjssiantjm (d'Orbigny), 1850. (PI. II. figs. 3-5.) 



1841. ? Samites plicatilis, F. A. Eoemer (non Sowerby), ' Verstein. norddeutsch. 

 Kreidegeb.' p. 94, pi. xiv. f. 7 ; 1843. H. B. Geinitz, ' Die Verstein. von Kieslings- 

 walda,' p. 8, pi. v. f. 2 ; 1845. A. E. Reuss, ' Verstein. bohra. Kreideformat.' p. 2B r 

 pi. vii. f. 5, 6. 



1843. Turrilites polyplocus, var., H. B. Geinitz, 'Die Verstein. von Kieslings- 

 walda,' p. 8, pi. v. f. 4. 



1845. ? Turrilites Astierianus, A. E. Reuss, ' Verstein. bobm. Kreideformat.' p. 24, 

 pi. vii. f . 7 ; 1852. C. G. Giebel, ' Fauna der Vorwelt,' vol. iii. p. 345 (partim). 



1846. Samites armatus, H. B. Geinitz, ' Grundriss der Versteinerungskunde/ 

 p. 304, pi. xii. f. 3 ; 1850. H. B. Geinitz, ' Das Quadersandst. oder Kreidegeb. in 

 Deutscbland,' p. 122 (partim) ; 1852. C. G. Giebel, 'Fauna der Vorwelt,' vol. iii. 

 p. 296 (partim). 



1850. Samites Astierianus, H. B. Geinitz, ibid. p. 120 (partim). 

 1850. Samites JReussianus, A. d'Orbigny, ' Prodr. de Paleont.' vol. ii. p. 216. 

 1850. ? Turrilites Beussii, A. d'Orbigny, ibid. p. 216. 

 1850. ? Turrilites plicatilis, A. d'Orbigny, ibid. p. 216. 

 1850. Selicoceras polyplocus, A. d'Orbigny, ibid. p. 216. 



1861. Anisoceras Betcssianus, F. J. Pictet and G. Campiche, ' Descript. des Foss. 

 du Terr. Cret. des Envir. de Ste. Croix ' (Paleont. Suisse, ser. 3, part 2), p. 76. 



1870. Selicoceras annulifer, F. Romer, ' Geol. von Oberscblesien,' p. 320, 

 pi. xxxvi. f. 2. 



1871. Seteroceras Eeussianum, C. Scbliiter, 'Cepb. oberen deutsch. Kreide,' 

 p. 109, pi. xxxii. f. 13-21, pi. xxxiii. f. 1 ; 1878. C. Barrois, Ann. Soc. Geol. du Nord, 

 vol. v. p. 404 ; 1887. A. Peron, ' Notes pour servir a l'Hist. du Terr, de Craie,' Bull, 

 Soc. Sci. bist. et nat. de l'Yonne, ser. 3, vol. xii. p. 138. 



1 ' Pal. Fran ? . Terr. Cret.' vol. i. p. 554. 



2 Prodr. de Pal. vol. ii. p. 102. 



