GONIATITES. 



MOLLUSCA. 



31 



sides bending somewhat abruptly towai'ds the body ; septa 

 delicately marked and waved on the edge ; with a short 

 dorsal lobo, and the dorsjl sinuses acute ; first lateral lobe 

 considerably rounded. 



Found at Black Hall, Bolland, Queen's County, Ireland. 



■21. G. BiDORSALis. — The Double Backed Goniatito, 

 pi. XXI. fig. 53, 54. 



Goniatiles bidoisalis. Phillips, Geology of Yorkshire, II. 

 p. 235, pi. 20, fig. 2, 3, 4. 



Subglobcp, umbilicate ; inner volutions entirely concealed ; 

 sides rounded, with transverse, sigraoidal, sharp ribs, which 

 curve elegantly backwards before passing over the rounded 

 ambit, and liaving line spiral, distant striie ; uniljilieus large, 

 the lateral lobes and sinus rounded, with a double dorsal 

 lobe, each part divided. 



This species may be confounded with the young of 

 Goitid/iles vorkibiles, but the difl'erent form of its septa dis- 

 tinguishes it I'rom that species. 



Found in Shale, at Woodford. 



28. G. MUTABiLis The Mutable Goniatite, pi. XXI. 



fig. 55, 56. 



Goiiialiles mulabilis. Phillips, Geology of Yorkshire, II. 

 p. 236, pi. 20, fig. 24, 25, 26. 



Subglobose, umbilicate ; inner volutions entirely concealed ; 

 sides and ambit much rounded, and smooth with direct 

 constrictions ; aperture transverse, semilunar ; umbilicus large, 

 with an acute margin ; first lateral lobe nai'row. 



The young shell is discoideo-cylindrical, very smooth 

 and shining ; umbilicus wide and acute, exhibiting the sides 

 of all the inner volutions, four in number ; aperture trans- 

 verse, widest and pointed next the ambit, and the constric- 

 tions direct. 



Locality unknown. 



29. G. iMPLiCATUs — The Involved Goniatite, jil. XXI. 

 fig. 58. 



Gonialites implicatus. Phillips, Geology of Yorkshire, II. 

 p. 235, pi. 19, fig. 24, 25. 



Subglobose, umbilicate ; inner volutions entirely concealed ; 

 sides a little flattened, with delicate transverse striaj ; umbi- 

 licus rather small, septa numerous, with their edges but 

 moderately waved ; first lateral lobes widely rounded, with 

 their dorsal margins parallel ; and having a ver^' small dorsal 

 lobe, with rounded dorsal sinuses. 



Found at Black Hall, Bolland, Queen's County, Ireland. 



30. G. PLATYLOBUs. — The Wide Lobed Goniatite, pi. 



XXI. fig. 59. 



Gonialites platylobus. Phillips, Geology of Yorkshire, II. 

 p. 235, pi. XX. fig. 5, 6. 



Subglobose, umbiliciite ; inner volutions wholly concealed ; 

 sides and ambit rounded, with obsolete spiral strite, and 

 crossed by direct constrictions ; umbilicus of moderate size, 

 crenate at its margin ; having rounded sutural lobes and 

 sinuses, and a wide dorsal lobe. 



Found at Bolland, Queen's County, Ireland. 



31. G. CALYX — The Calyx Goniatite, pi. XXI. fig. 60, 

 61. 



Gonialites cah/x. Phillips, Geology of Yorkshire, II. p. 

 236, pi. 20, fig. 22, 2.3. 



Discoideo-cylindrical, umbilicate ; with about five volu- 

 tions, which are entirely enveloped in the body or outer one ; 

 ambit nearly flattened, glabrous, with delicate transverse strix ; 

 umbilicus very wide and acute, and deep, exposing within it 



the margins of the volutions ; and frequently crenate at the 

 edges ; aperture subluniform, flat, transverse, and acute at 

 the outer angles ; constrictions direct, having round septal 

 undulations ; the dorsal lobe and sinuses forming a waved 

 transverse line. 



Tliis is the young condition of the fossil ; the adult is not 

 known. 



Found at High-Green Wood, Black Hail, and Kulkcagh. 



GicNus VI.— SCAPIIITES.— P«/-A«,wo-/. 



Shell chambered, involute ; its first volutions sniuli, 

 and incvciibing very gradually, its last elongated and 

 dilaled or expanded, and then diminishing and inflated ; 

 the divisions of the ehainbers lobed and sinuous. It 

 appears to be almost, if not wholly, internal. 



1. S. STRIATUS. — The Striated Seaphite, pi. XXII. fig. 1, 

 2,3. 



Scaphitcs attio.lus. Mantel!, Geology of Sussex, p. 119, 

 pi. 22, fig. 3, 4, 9, 11, 13, 14, 15 and 16. De la Beche, 

 Geo. Manuel, p. 293. Fleming, Brit. .\n. p. 249. 



Inner volutions umbilicate, deeply inserted, and wholly 

 concealed by the outer volution ; ambit or back tumid, 

 suddenly enlarged, and the reflected turn terminating before 

 reaching the centre ; aperture entire, of an irregular trans- 

 verselj' ovate form and marginate ; margin prominent, and 

 upper part produced, extending a little over the spire ; whole 

 surface covered with numerous oblique, annular, bifurcate 

 striae, which arise singly from the inner margin, divide into 

 two or three before passing over the ambit, and unite with 

 those which correspond on the opposite side ; inner iialf of 

 the outer volution somewhat depressed, and from thence the 

 striae extend obliquely in a radiating manner, and become 

 bifurcate at the edge of the depression ; towards the ajier- 

 tnre the slrise are larger and more distinct, septa sliglitly 

 concave, with three principal indentations on their edges, 

 and with several minute sinuosities. Situation of the 

 siphuncle unknown, but it seems to have been on the 

 internal margin. Length about an inch, greatest thickness 

 one-fourth, and its width an eighth of an inch. 



Found in the Gray Chalk Marie at Hamsey, Ranscombe, 

 Rodmill, and Brighton. 



2. S. cosTATUs The Ribbed Seaphite, pi. XXII. fig. 4, 



5. 



Scaphites cosialtis. Mantell, Geology of Sussex, p. 120, 

 pi. 20, fig. 8 aTid 12. Fleming, Brit. An. p. 241. De la 

 Beche, Geo. IVIanuel, p. 293. 



Volutions convex, laterally compressed ; inner volutions 

 wholly inserted and concealed ; sides with numerous trans- 

 verse furcate strias, \i liich embrace the ambit ; sides of the 

 outer volutions smooth, and provided with eight or ten 

 distant oblique nodular projections ; ambit broad, convex. 

 Length one inch ; width an eighth of an inch ; thickness of 

 the ambit a sixth of an inch. 



This species is not so delicate as <J>'. slriatus, and is dis- 

 tinguished from it by the nodular projections on the sides of 

 the outer volutions ; these proceed from the centre, and 

 diverge into numerous stride and encircle the ambit, which 

 is broad, and the projecting terminations of the striae pro- 



