ALARIA PALMATA. 65 



Cornbrash matrix. It bears the name A. composita, in Lycett's handwriting, but 

 has been recorded as J. hamus, var. phillipsii, which has a different form of wing, 

 etc. Another specimen, showing' the shell and the wing, but both of them 

 chemically worn, is in Mr. B. Thompson's cabinet from Qninton, North-ants. 

 The cast may probably be recognised by (1) its agreement in proportions ; (2) the 

 spiral swelling rising gradually higher in the whorl ; (3) the apex being screw-like 

 (cochlcate) ; and (4) the gibbosity opposite the left side of the aperture. In this 

 case the species occurs at Bedford (see PI. VII, fig. 8). 



The species is closely allied to Maria denticulata (Piette, loc. cit, pi. xvi, 

 figs. 4-8), with which the author includes the A. hamus of Morris and Lycett. 

 It certainly belongs to that group, but is more angular exteriorly when well pre- 

 served, and has a shorter wing, and in any case the name composita, not considered 

 by Piette, has the priority. This species is quoted under Piette's name from the 

 Cornbrash of Boulogne. 



Alaria palmata, sp. nov. Plate VII, fig. 0. 



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 imbedded 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 prepenultimate whorl, making a wall of shell 

 behind the aperture. It also extends forwards half way down the canal sheath, 

 and then is cut 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 the rubbly Cornbrash of the "Woodstock railway cutting at Shipton-on- 

 Cherwell, and is in the collection of Mr. Hudleston. 



Distribution and Relations. — The character of the wing of this species removes 

 it from all the 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, to Aporrhais pagoda of Morris and 

 Lycett in respect of its wing, though different in all other respects. 



