194 Dr. G. J. Hinde — Western Australian Fossils. 



2. Corals and Polyzoa. By George J. Hinde, Ph.D., F.G.S. 



Genus Amplexus, Sowerby. 



Amplexus ptjstulosus, Hudleston. 



1883. Amplexus pustulosis, Hudleston, Q..J.G.S. vol. xxxix. p. 591, pi. xxiii. 

 figs, la-le. 



There are several compressed and crushed fragments of this species, 

 which agree in every respect with the forms figured by Mr. Hudles- 

 ton, save that they have none of the surface spines or nodes, from 

 which the species derives its name. These processes, however, are 

 not essential to the species, since they are not present on some of the 

 figured type examples, which, through the kindness of Mr. Hudles- 

 ton, I have had an opportunity of examining. The specimens, 

 when uncompressed, are from 25 to 30 mm. in diameter. There are 

 about 40 septa ; at the summit of the calice they are 2 mm. apart, 

 from centre to centre ; lower down from 1-5 to 1*75 mm. In some 

 instances in the lower portion of the coral, the septa become so 

 thickened by sclerenchyma as to be laterally in contact. The outer 

 surface, when un weathered, merely exhibits annulations of growth 

 and fine epithecal stria? ; the weathered examples show vertical lines 

 and furrows, which are the exposed exterior margins of the septa. 



Distribution. — Carboniferous Limestone, Gascoyne Eiver. 



Genus Cyathophtlltjm, Goldfuss. 

 Cyathophyllum virgatum, Hinde, sp.n. Plate VIII. Figs, la, lb. 



Corals simple (?), subcylindrical, elongated, straight or curved. 

 About 56 septa, half of which are long and reach nearly to the centre 

 of the calice ; the others only reach from one-third to one-half that 

 distance ; there are about five septa in three millimetres. The 

 septa are thick near their parietal margins, but somewhat rapidly 

 diminish in size, and for the greater part of their length are very 

 thin. They are connected by very stout dissepiments, which form 

 a well-marked exterior zone to the calice. The wall is apparently 

 formed by the lateral extension of the septa. The septa are ap- 

 parently bilaminate, but the median line is not distinctly shown in 

 sections. The outer surface of the coral is smooth or with faintly- 

 marked longitudinal ridges, which correspond with the interspaces 

 between the septa. When the surface is weathered, as in the 

 specimen figured (Fig. la), the exterior margins of the septa appear 

 as vertical lines connected by the dissepiments. 



There are several imperfect examples of this species ; the longest 

 measures 70 mm. by about 11 in diameter. One specimen is 

 partly covered by Aulopora repens. The specimens are now all 

 simple, but it is not impossible that they may originally have formed 

 fasciculate, compound colonies, like those of Cyathophyllum cojspntosum, 

 Goldf. Though the character of the septa in this and the next 

 species corresponds with that of the typical forms of the genus, it 

 is doubtful whether the wall in these Australian forms is structurally 

 similar to the Eifelian types ; it is relatively much thicker than those 

 with which I have been enabled to compare it. 



