PALAOZOIC. PTEROPODA. CAMBRIAN AND SILURIAN. 
CAMBRIAN. LOWER SIL. UPPER SILURIAN. 
1 
J 
Upper Ludlow. 
e Lmst. 
Aymestry Lmst. 
SPECIES. 
REFERENCES. 
‘Wenlock Lmst. 
Tilest. & Passage. 
Llandeilo. 
Low. Llandovery. 
| Har. St. David’s. 
Caradoe or Bala. 
Wenlock Shale. 
| Lower Ludlow. 
Menevian. 
| Lingula Flags. 
Tremadoc. 
Pass up. 
Up. L 
Woo 
Sub-Kingdom, MOLLUSCA. 
Prov. ODONTOPHORA. 
Class, PTEROPODA. 
Aporobranchiata, Blainville. 
THECOSOMATA, 
HYALEID2. 
Centrotheca ......... Salter, US6O sc. teesl coalesce peas pod =a ed G05 ses[ece{ees{eveleee[eee{.e-[--.| Sub-genus of Theca (vide). 
Cleidotheca ......... Salter, 1866) ..5).5:|:.s\e<c|e.+].<s Bal asd ber ses[essleee[eaelsee{eee]-.[ee.] Sub-genus of Theca (T. operculata). 
HYALEID=. THECOSOMATA. 
Conularia ......... Miiller, 1818... 
— cancellata ...... Sandd.  .i..60<. Fon eal oc) (ane soe seal ae [ecel [ove {ees|eee|aee{eee]eee]e-]eo.| Leonh, and Bronn. Jahrbuch, 1847, p. 20, t.1, f£.11. ?P C. 
quadrisulcata, Sow. Sil. Syst. t.12, f. 22. C. cancellata, 
M‘Coy, Brit. Pal. Foss. p. 287. 
— corium..........6+ ISGLES Tee decrw asec Beal lecel 6O0| food (3! food anal lead (86 v2) Geel ese|seclees|cesln |e) Mem. Geol. Surv;, volu:iit, p..3555 t-W0-A, 1. 12. 
— elongata ......... 7 Hira Benonteecoee bod fag) os las Be meallGe eed d ass ser[acs]ece|eee]ees[ece]ese].-2] Geol. Rept. p. 393, t. 29 A, £.2; ib. Salt. Siluria, 4 ed. 
p. 199, Foss. 41, f. 3. 
— Homfrayi ...... SQUID ncersczee es pel sal loes| kat (eS! Goel lee lee (eae seafece[ece|oee{sosfecs]eee].ee] Mem. Geol. Surv. vol. iii, p. 354, t.10, £. 11-13. 
— Llanvirnensis... Hicks ............ SoH lasel loa Iooe) FA fac] lnc lane (bee ieve|coMuce|ess|.eo]oes|aae| es] Q- Se Geol. Soc. vol. xxxi, p.189, t.11, £. 5,6. 
— levigata ......... SALE. Gestceresces: Sel fecal ed lod Es S581 AN load os seclece[eceleee|ees{eee{eee]-e-] Mem. Geol. Surv. vol. iii, p. 354, woodcut 19. 
— margaritifera... Salt, .2.......... 263 [ea soe lod Resi laticl noel ase] ore Korlcc|eallseelaee|eealiene|eae|LemeiGeols Sarva vol. ain, pass s.t.0r A, £02. 
— pyramidata...... Degli cvatesss eles ese | eel a ealePi| ee |ee weeleee[ese]eeefeee]eee[eee]-e-] Doubtful species (Budleigh). 
— quadrisvkcata,., Sow. .....0..0.5 Baa oa load leaet aes ancl Vide C. Sowerbyi. 
— Sowerbyi +1... Defr. w....c.000. er al lal hee tas veel x |e feeelaee| ae | x Jeee{eee| a {---[...| Troost. 5th Rept. on Tennessee, p.53. C.quadrisuleata, Sow. 
Sil. Syst. p. 626, t.12, f. 22; ib. Min. Conch. t. 260, 
f. 3, 43; ? ib. Portl. Geol. Rept. p. 393, t. 29 A, f. 3. 
C. Sowerbyi, Siluria, 4 ed. t. 25, f.10, and De Blainv. 
Malacol. p. 377, t. 14, f. 2; ib. De Vern. and De Key- 
serling, Géol. de la Reusse, 1845, vol. ii, p. 348, t. 24, 
£753 
— subtilis ......... Dali: ze wcceusesss pod ec leod eer, feos 2 Berl eel bee seslsce{oeefeee|eeel ae [eeefoee| M‘Coy, Brit. Pal. Foss. App. A, p.vi, t.1 L, f. 24, and 
p. 228, in Text. 
Gr esets nt. eeccccessnee Rang, 1827 
— PTIMBA v.06. Forbes .....005 04 |pcd) fobAl food 000 300] [aoe Iba0) face noel lon) food ose 
— Sedgwickii ...... SRORDES wece canes 24| Ince) Ito joad fa $04] jong kod Iooe ses[ove}ess[ooelece|ece]eee[eoe| } Vade Orthoceras. 
— ventricosus ...... Sharpe .....0.0- 30540) oc lobed os bealie 
HYALEID=. THECOSOMATA. 
Cyrtotheca ......... Balter s...ccsceses|cas|eee Aro las boc hes|aes| oct [oes secleceleceleae|eeslece[eee]eee| Vede Q.J. Geol. Soc. vol. xxviii, p.179; ib. vol. xxvii, p. 397- 
— hamula ..,...... SHACKS cccasscuvers o¢0| |e 3] 80 lod ead Ba ocd eel Ree seslese[ecefece|cneleos]eesfe,-] Q. J. Geol. Soc. vol, xxviii, p.179, t. 7, £.14. 
YOuites  .scsseess Eichwald, 1840)...|... Pea reel bas Galtceel eel eg seiligea|eee was[eccleee[eee|s..| Vade Theca, 
en 
al Er 
