ALARIA, 115 
—mostly from P, (page 31). Specimens showing any of the processes (6 c, 6 d) 
are rare. The specimen 6 d differs somewhat from all the others, and approaches 
the var. Phillips in some respects, and still more reminds me of the form provi- 
sionally described as Al. spinulosa. I think that Al. hamus, as defined above, is 
mainly confined to the upper division of the Inferior Oolite, at any rate in Dorset- 
shire. Elsewhere in England, except perhaps at Dundry, it appears to be represented 
either by the variety Phillipsii, or else by dwarf forms, like those to which I now 
direct attention. 
33. Dwarr VARIETIES OF ALARIA HAMUS. Plate IV, figs. 7 a, 7 b, 7 ¢. 
Specimens from the Parkinsoni-zone of Notgrove (fig. 7 a) and from the Parlkin- 
soni-zone of Horton Hill (Upper Trigonia-grit) are fairly similar. The dwarfing 
extends to all the whorls, the whole shell is proportionally smaller, and the large 
spirals on the anterior portions of the whorls are always three in number. The keel of 
the body-whorl possesses the spinous lumps characteristic of Al. hamus, but they are 
better shown in specimens from Horton Hill than in the more slender ones from 
Notgrove, which might indeed be regarded with equal justice as dwarfs of the 
variety Phillipsii. 
The specimen from Horton Hill (fig. 7 >) is sufficiently well preserved to 
show that it was possessed of a wing and “ tail” in all respects, except as to size, 
identical with Al. hamus. The evidence of a wing in the case of the Notgrove 
specimens is less clear, but the plain and strongly-keeled body-whorls show that 
the specimens are mature shells. 
The specimen (fig 7 a) from the Gryphite-grit of the neighbourhood of Stroud 
presents other differences. The shell is shorter in proportion to its width, and 
seems to have matured earlier; the whorls are strongly muricated. In this speci- 
men the three spirals which occupy the anterior portion of the whorls of the sptre 
are so conspicuous that, if a trivial name be required, I would suggest that of 
TRICINCTA. 
The specimen (fig. 11), also from the Gryphite-grit, is most probably an imma- 
ture form of Al. Phillipsii. Such forms are not uncommon in the Scarborough 
Limestone, and these of course are referred to Al. Phillipsii in default of better 
evidence. 
It should be noted that, while the full-grown and typical forms of Al. hamus 
occur in the Dorset district, these dwarfed varieties seem to take its place in the 
Cotteswolds. 
