A. E. Trueman — The Lias of South Lincolnshire. 103 



A. sp. 



" Androgynoceras" aff. maculatum, 

 Y. &B. 



A. cf. capricornihm, Wt. (abundant). 

 Belemnites clavatus, Blainv. 



B. inilleri, Phill. 

 Avicula incequivalvis, Sow. 

 Leda sp. 



Lima eucharis, d'Orb. (rare). 

 Pecten cequivalvis, Sow. (common). 

 Protocardium tnmcatum, Sow. 

 BliyncJionella cf. rimosa, Qu. 

 Cristellaria crepidula, F. & M. 



C. sp. 



Dentalina brevis, d'Orb. 



D. communis, d'Orb. 

 D. cf. nodosa, d'Orb. 

 D. glandulosa, Terq. 

 D. spp. 



Frondicularia Terqiiemi, d'Orb. 

 F. intumescens. Born. 

 Lingulina tenera, Born. 

 Marginulina Bomeri, Reuss. 

 Nodosaria raphanistrum, Linn. 

 N. sp. 

 Trochamina sp. (?). 



A similar fauna characterizes the lower beds exposed at Brace- 

 bridge, a mile north of Waddington, but this section is more 

 couveniently considered later. 



3. Middle and Upper Lias, 

 A. Lincoln District. 



The best exposure of Middle Lias and contiguous deposits in this 

 area is seen at Bracebridge Bi-ick Pit, about three miles south of the 

 Cathedral, Lincoln, where the following section is exposed: — 



ft. in. 



Grey paper shales, weathering orange, with layers 

 of flat, green nodules containing Inoceramus. 

 Dachjlioceras cf. tenuicostatum, D. semicelatujn, 

 Posidonomya bronni . . . . . . 15 



Impersistent band of dark earthy nodular limestone, 

 with well-preserved Posidonomya bronni. " Cone- 

 in-cone " structure ...... 3 



Greenish shale with Tiltoniceras acutum, T. costatum, 

 Dactylioceras athleticnm. D. cf. tenuicostatum, 

 Lexytcena sp. ....... 4 



Light-grey shale with Dactyloids (D. athleticum, 

 D. cf. hollandrei), Protocardium sp., Goniomya 

 hybrida . . . . . . . .28 



Light-grey shale with scattered phosphatic nodules ; 



Paltopleuroceras spp. . . . . . .10 



Layer of ferruginous nodules with many phosphatic 

 nodules ........ 6 



Light-grey shales with scattered phosphatic nodules ; 

 Paltopleuroceras spp. ; some beds full of Proto- 

 cardium truncatum, Dentalium giganteum, and 

 Goniomya hybrida . . . . . . 14 



Main Nodule Bed ; variable, but usually consists of 

 two beds of brown ironstone separated by green 

 shales with phosphatic nodules. Pecten cequivalvis, 

 P. hmularis, Avicula cygnipes, Leda {Nuculana) 

 graphica, Belemnites s.^., Bhynchonella s^. . .24 



Grey shales with Paltopleuroceras spp. Many 



Lamellibranchs . . . • . . .20 



Dark-grey micaceous shales with layers of ironstone 

 nodules. Amaltheus 7nargaritatus, A. gibbosa, 

 A. Icevis, Seguenziceras spp., Modiola scalprum, 

 Nuculana Quenstedti, Ostrea sp., Oresslya spp., 

 Plicatula sjnnosa, P. calvus, Eucyclus imbricatus, 

 Cryptcznia consobrina . . . . . . 15 



temiicostatwn 



sub-zone. 

 15 ft, 3 in. + 



acutum sub- 

 zone, 3 ft. 



spinatum 



zone. 



19 ft. 10 in. 



viargaritatus 

 zone. 30 ft. 



