ACTION TNA. 475 



1851. AcT.EONiNA GIGANTEA, Deslongchamps. Morris and Lycett, Grrt. Ool. 



Moll., part 1, p. 119, pi. xv, 



fig. 13. 

 1885. — — — Hudleaton, Geol. Mag., 1885, 



p. 203. 

 1895. — — — Cossmanu, Gast. Terr. Jur., p. 22, 



pi. ii, figs. 12, 13. 

 Syn. — DESLOKGCHAiiPsii, cVOrligmj. Terr. Jur., vol. ii, p. 171, 



pi. cclxxxvi, fig. 11. 



Bibliography, Sfc. — The Normandy specimens (Bathonian) are mainly casts. 

 The very large specimens from the Inferior Oolite of the Yorkshire coast are 

 broader than the French types. This is one of the few species for which the 

 generic name, Actgsoiiina, is retained by M. Cossmanu, 



Description. — The specimens from our Inferior Oolite are variable as to size 

 and shape. The Yorkshire specimen figured by Morris and Lycett has a height 

 of 40 mm., whilst the specimens figured in the accompanying plate do not exceed 

 25 mm. The spiral angle may be said to range from 52° to 60°, whilst the body- 

 whorl is generally less than two-thirds the total height. 



The shell is oval, thin, and smooth, whorls (seven or eight) rather flattened at 

 the sides, sub-convex, with the posterior tabulation slightly rounded off; aperture 

 narrow above, dilated below, and about three-fifths the entire length. 



Relations and Distribution. — This may be taken as an average representative 

 of the genus Actseonina, closely related to the cylindro-conical forms {Gylindro- 

 hullina), yet passing by protraction into such forms as Actseonina acuta, d'Orb. 

 Besides the Yorkshire specimens, there are some from the ParJcinsoni-zone 

 of the Cotteswolds (fig. 2), which are rather short in the spire and approaching 

 Act. Scarhurgensis. This variety of Act. gigantea I have noticed on several 

 horizons and localities of the Inferior Oolite ; it is an intermediate form. 



Fig. 3 from the Dean and Chapter Pit at Lincoln {Mnrchisonse-zone) may be 

 taken as a small but more typical representative of the species ; whilst in Fig. 4 

 (specimen also from Lincoln), where the spiral angle is reduced to 45°, we have 

 the variety attenuata, which might almost be regarded as a distinct species. 



423. AcTJiONiNA ovATA, Lycctt, 1850. Not figured. 



1850. AcTiEONiNA OTATA, Lt/cett. Anu. Mag. Nat. Hist., 2ud ser., vol. vi, p. 418. 

 1853. — — — Proc. Cotteswolds Nat. Club, vol. i, p. 79. 



This species is not enumerated by Morris nor by Hudleston and Wilson. 

 There is one very poor specimen in the Jermyn Street Museum, from the Inferior 



