202 W. H. Hudleston — On the Torkshire Oolites. 



85. — AcTiEONiNA HUMERALis, PbilHps, 1829. Plate V. Figs. 1, la, 3. 



1829 and 1835. Actceon Jmmeralis, Phillips, G.Y. p. 129, pi. xi. fig. 34. 



1849. Actmonina humeralis, D'Orb. (PML), Prod. i. p. 264, Et. Baj. 



1854. Actaon humeralis, Phil., Morr. Cat. p. 233. 



1875. Actceon humeralis, Phillips, G.Y. 3rd ed. p. 260, pi. xi. fig. 34. 



Compare also 

 1852. Actceonina Sarthacensis, D'Orb. Terr. Jurass. vol. ii. p. 167, pi. 



286, figs. 1 and 2. 



1876. Actceonina chrysalis. Tate and Blake, Yorkshire Lias, p. 356, pi. 



X. fig. 23.' 

 Bibliogra'pJiy, etc. — Phillips's type belonged to Bean, and is 

 amongst those preserved in the York Museum. 



Descriptions. — Specimen from the Dogger (zone 1), Peak (Blue 

 Wyke). York Museum. Figs. 1, la. ? the type. 



Height 15| millimetres. 



"Width in proportion to height 48 : 100. 



Spiral angle 66°. 



Length of body-whorl to total height 71 : 100. 



N.B. — The specimen is a trifle compressed, and half-skinnod. 

 Shell ovate-oblong and composed of about 6 whorls. The spire 

 occupies three-tenths of the entire height, and increases vi^ith toler- 

 able regularity ; suture rather oblique. The whorls of the spire are 

 flat atop, and mai'ked on the shoulder by a grooved line, which 

 produces two steps, or a double tabulation ; sides of the whorls sub- 

 compressed. The groove on the shoulder is very distinct in the 

 body- whorl, which is large and cylindrical, and in its present con- 

 dition smooth, or at most marked with indistinct lines of growth. 

 Faint indications of spiral ornament may be noted in the base. 



The length of the aperture is about two-thirds the height of the 

 shelL It is narrow behind, wide in front: outer lip straight {Or- 

 thostoma), columella smooth and slightly encrusted, but without 

 plications ; termination of the aperture evenly rounded.^ 



Another specimen. — From the same horizon, locality, and collec- 

 tion. Fig. 3. 



( Height , 12 millimetres. 



Approximate < Width in proportion to height 43 : 100. 



( Spiral angle 62°. 



Seven whorls may be counted, and probably the specimen con- 

 tained eight. The spire is very sharp and well preserved, and the 

 double tabulation produced by the grooved line on the shoulder of 

 the whorls conspicuous. A fine system of striato-punctate lines is 

 visible on the body-whorl, and these are rather stronger towards the 

 base, especially in the region of the columella. 



Another specimen. — Same horizon and locality, Leckenby Col- 

 lection. Not figured. 



This one is 28 mm. in height, being nearly twice the size of the 

 specimen first described (Fig. 1), which is an unusually fine one. 

 1'here are no indications whatever of spiral ornament : indeed the 

 smaller shells usually show the fine spiral lines better than the 



1 It might seem superfluous to enumerate some of these points, -which are 

 characters of the genus ; but since this species is still quoted as an Actceon in the 

 last edition of the Geology of Yorkshire, a full description is the more necessary. 



