Dr. G. J. Einde — Western Australian Fossils. 197 



Plerophyllum sulcatum, Hinde, sp.n. Plate VIIIa. Figs. 2, 2a. 



Corallum curved, approximately subcylindrical, showing in the 

 upper portion repeated renewals of growth. The only specimen, 

 which is imperfect, is 40 mm. in height and 11mm. in diameter. 

 There are in all 28 septa, of which 4 are prominently developed 

 and the others are subequal. The cardinal or dorsal septum is large ; 

 between it and the alar septa there are on one side 7, and on the 

 other 8 smaller septa, whilst the large counter-septum has between 

 it and the alar septa 4 smaller on one side and 5 on the other. 

 The septa are about 1 mm. apart; they are of precisely the same 

 characters as in P. australe, and they are similarly inclosed and 

 consolidated by stereoplasm, so that in a transverse section of the 

 lower portion of the coral the individual septa can only be recognized 

 by their median lamellae (Fig. 2a). 



The outer surface in this species has well-marked longitudinal 

 ridges and furrows about half a millimetre in width, which appear 

 to be quite independent of the septa. 



There is only a single example of this species in the collection. 

 From P. australe it is readily distinguished by not having more than 

 four prominent septa and by the different characters of the outer 

 surface. 



Distribution. — Carboniferous, Irwin Kiver, Little Champion Bay, 

 Victoria District. 



Genus Pachypora, Lindstrom. 

 Pachypora tumida, Hinde, sp.n. PI. VIII. Fig. 3. 



Corallum branching ; branches subcylindrical, tumid ; ranging 

 from 10 to 13 mm. in diameter. Corallites nearly circular in section ; 

 walls moderately thick, both in the central portions of the branches 

 as well as near the surface ; calices elongate-oval, subcircular or 

 rhomboidal, about 1 mm. in diameter, moderately oblique to the 

 surface. No septa or septal spines shown ; tabular apparently few 

 and complete ; mural pores rare. 



There is but one fragment of this species in the collection ; it is 

 about 40 mm. in length. The weathered upper surface shows the 

 calices in fairly good preservation. From its surface aspect, this 

 form would perhaps be regarded as belonging rather to Alveolites 

 than to Pachypora ; but judging from the thickened walls of the 

 tubes, it may more properly be included in this latter genus. The 

 calices however look much more like Alveolites than those of P. cer- 

 vicornis, De Blainv., and they are larger and more oblique than in 

 P. meridionalis, Nich. & Eth. jun. (Ann. & Mag. Nat. Hist. ser. 5, 

 vol. iv. (1879) p. 280). On the other hand, the calices are less 

 oblique and less regular than in Alveolites (Cladopora) robusta, 

 Eominger (Fossil Corals, Geol. Surv. Michigan, p. 54, pi. 32, figs. 

 1, 2), which is regarded by Nicholson, though not with absolute 

 certainty, as referable to Alveolites. As regards its mode of growth, 

 P. tumida stands on the boundary-line between Pachypora and 

 Alveolites. 



Distribution.— Devonian ? Opposite Mount Krauss, Kimberley 

 District. 



