Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/366

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258 PROCEEDINGS OF THE GEOLOGICAL SOCIETY.


? Teuthis. Pl. XVI. fig. 8.

Small portions of the shaft of a pen with the lateral expansion of the wings indicate the presence of a Cephalopod allied to the Calamaries. The remains I have noticed are all very fragmentary, the largest being figured as above. They are from Wollumbilla.

Australian Belemnites.

Note by Prof. John Phillips.

Of three species which are in the Australian collection sent me by Mr. C. Moore, the first, a large phragmocone typical of the Oolitic system (meaning by this the whole series of beds from the Middle Lias to the Kimmeridge Clay inclusive) is 5.5 inches long, its greatest diameter 1.75, the section nearly circular. Above forty septa can be counted ; and the whole number must have been fifty, without reaching the last chamber. The septa are a little oblique, advancing in the dorsal and retiring a little on the ventral face, with a slight lateral flexure. Depth of the chambers about one-sixth of the diameter. Siphuncle clearly internal, its section rather elliptical.

The phragmocone is nearly straight, with an angle of 18°.

Of the guard only a slight indication of a subcentral axis can be recorded. I cannot at present assign its distinctive characters. Wollumbilla.

The second species occurs in Queensland, and is represented by several frusta of the guard, but no phragmocone. It is not identical with any European or Indian form known to me.

67. Belemnites australis, sp. n. P1. XVI. figs. 1-5.

Guard hastate, depressed in the postalveolar region by lateral expansion ; ventral face somewhat flattened, but without trace of a ventral groove; two lateral grooves sharply cut, and approximating to the ventral face in the alveolar region, thence bending toward the dorsal aspect, and continued in a fine stria on the middle of the side (figs. 1, 2).

Length 4-1/2 inches to the point where the guard grows thin over the phragmocone ; diameters at the alveolar apex 0.725 and 0.600, further back in the more flattened part 0.770 and 0.600. Axis of the guard 3.300.

Proportion of axis to ventro-dorsal diameter as 550 to 100, of ventral to dorsal radius 40 to 60.

Phragmocone unknown. Its angle 20°. A younger specimen, marked "Ward, C. K.," is more distinctly hastate, and shows the flexure of the lateral groove more clearly than the others from "Queensland." Figs. 3, 4.

A much older specimen, also marked "Ward, C. K.," is a split half, the fissure being dorso-ventral. It shows the lateral groove, marked with a double stria, and the nearly straight-sided exceutric alveolus. The axis of the guard is curved, and channelled, as in some specimens from the Oxford Oolite. The ventral portion is to the dorsal as 40 to 60 ; the axis, as is usual in old specimens of hastate