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of the larger end 0.17 mm., and the smaller 0.12 mm. At first sight the larger termination of this peculiar form appears to have been furnished with radiating arms, but in reality these extensions seem to be only irregular lobes or swellings, similar in charactei to those at the smaller end of the specimen. In other fossil examples of this genus great inequalities in the form and size of the aim terminations are known; thus, for instance, in A. incequale Rüst from the Lower Devonian (Pal. Bd. xxxviii, p. 170, pl. xxiii, fig. 10) the expansion at one end is more than doublé that at the other.

Rare; in red jasper at Mount Badau, near the mouth of the Badau River.

Genus Dictyastrum Haeckel.

I he test consists of three equal, chambered, arms radiating from a centre, in which, in some instances, a chamber is present.

Dictyastrum desecatum, Rüst. Pl. II, fig. 13.

Rüst: I al. Bd. xxxiv, 1888, p. 200, pl. xxv, fig. 1 1.

The arms of the test slightly increase in width towards their distal ends; no central chamber can be recognized. The arms are truncate at the ends and furnished with two longitudinal rows of pores, and in the wider portions a thircl row can be seen. Length of arms o. 135 mm.; width at their ends 0.035 mm. In red jasper from Badau Mountain, near the mouth of the Badau River. Also from the Aptychus Schiefer (Jurassic), ot Urschlau, Upper Bavaria, and from the Neocomian of Gardenazza (Sl Cassian).

Dictyastrum speciosum, Parona. Pl. II, fig. 6.

I aiona: Boll. Soc. geol. Italiana, vol. ix, 1890, p. 29, pl. iv, fig. 1.

Test with three short robust arms and a largfe triancndar

1 o &

central area, but apparently without a central chamber. The arms terminate in a large globose expansion, and they have

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