Plate 9. Figs. 5, 6.

Caryocaris marrii Hicks, 1876, Quart. Journ. Geol. Soc., Vol. xxxii, p. 138. Jones and Woodward, 1892, p. 92, pl. xiv, figs. 16–18. Chapman, 1903, ? Rhinopterocaris maccoyi (Eth. fil), p. 117, pl. xviii, fig. 16. Chapman, 1908. Caryocaris marrii Hicks, p. 282, pl. —, figs. 4, 6. Chapman, 1912, p. 212, pl. xvii.

Observations.—This little phyllocarid is probably the most abundant form in the New Zealand collection. It is of especial interest to note the occurrence here of an example with conjoined valves spread out dorsally, a phase of its compression in the slates comparable with one figured many years ago from a Castlemaine specimen in the National Museum (Chapman, 1903, pl. xviii, fig. 16) under? Rhinopterocaris. In the specimen now figured (Plate 9, fig. 6), sufficient proof is seen that some of the wrinkling of the carapace in these phyllocarids is natural to the organism, and not necessarily a secondary result caused by a lateral crumpling of the rock. In other cases, however, there may exist such an artificial puckering, due to the condition of the surrounding matrix, when of the nature of a phyllite.

The other specimen figured is an elongated, typically crumpled or corrugated form, with a generally concave dorsal margin. The aspect of this fossil (Fig. 5) is probably from the left side, the blunt truncation indicating the abdominal junction, as in Hymenocaris.

Distribution.—Caryocaris marrii was first recorded from the Arenig Schists of Nanntle, S. Wales. In Australia, localities for this species are the Lower Ordovician rocks of Marong, near Daylesford, and erraties derived from a similar formation from Wynyard, Tasmania.