Original Description of Alaria palmata by Blake, 1905, p. 65:
- "Type. - Spiral angle 23°. Three whorls of the spire preserved behind the last; probably there were three more. Ornament of the hamus type - i.e. longitudinal ribs affecting the anterior half only - greatest in the penultimate whorl, dying out towards the apex, but reduced to denticulations of the posterior keel in the last whorl. This keel is gibbous on the radius perpendicular to the direction of the wing on the side of the aperture. The anterior keel comes to its maximum near the same spot and dies away on either side. The whole is crossed by 13 riblets per whorl, extending 4 or 5 riblets below the anterior keel, the canal sheath below being bare. It bends towards the wing and is of medium length. The outside of the wing is embedded and cannot safely be removed, but the keels must both die out without making any digitation. The wing extends backwards to the middle of the penultimate whorl, making a wall of shell behind the aperture. It also extends forwards half way down the canal sheath, and then is cit off squarely and the posterior border seems to be continued backwards like a horn. The wing is very thick and massive. The specimen is from rubbly Cornbrash of the Woodstock railway cutting at Shipton-on-Cherwell, and is in the collection of Mr. Hudleston."
Stratum typicum: "rubbly Cornbrash", Bathonian, Jurassic
Locus typicus: the Woodstock railway cutting at Shipton-on-Cherwell, Kidlington, South East, Great Britain
Comment Blake, 1905, p. 64:
- "The character of the wing of this species removes it from all ordinary forms of Alaria and makes one think of Aporrhais; but the posterior whorl of the shell does not seem to have been reflected on the inner lip of the aperture. It is comparable, however, ti Aporrhais pagoda of Morris and Lycett in respect of its wing, though different in al other respects."
Alaria palmata Blake, 1905, pl. VII, fig. 9a, b