Palaeozoic Corals from Northern Queensland. 277 



of them exhibit the characters of the surface. Moreover, 

 though the coralla are calcareous, and are themselves per- 

 meated by crystalline calcite, their more delicate structures 

 seem to have been destroyed during the process of fossiliza- 

 tion, and microscopic sections fail to show the internal struc- 

 ttire in a thoroughly satisfactory manner. 



The corallum in this form is ramose, the branches from two 

 to five lines in diameter, diverging from a main stem obliquely 

 or at right angles, the terminal portions always bifurcating, 

 and the apices of the branches rounded or lobate. The coral- 

 lites, after a short vertical course in the axis of the branches, 

 are abruptly deflected nearly at right angles ; and after hold- 

 ing this latter course for a space of from half a line to a line 

 or more, they open by direct apertures upon the surface. As 

 examined by a lens, the outer horizontal portions of the coral- 

 lites appear to be thickened at intervals, as in Stenopora ; but 

 thin sections do not confirm this view of their structure. On 

 the contrary, their walls seem to be uniformly thickened, the 

 thickening increasing in amount as the calices are approached, 

 and sections at right angles to the tubes appear to give clear 

 indications of the existence here and there of a series of inter- 

 stitial tubuli. Neither tabula? nor mural pores are recogni- 

 zable with any certainty. 



When fractured surfaces of this coral are examined, the 

 appearance presented is so Stenop>ora-\ike 7 that we feel our- 

 selves obliged to refer the species to Stenopora rather than to 

 Monticulipora, notwithstanding the absence of the more de- 

 tailed characteristic internal structure of the former genus. 

 It is, of course, just possible that this may be due to the 

 mode of preservation. The general aspect of this species is 

 quite that of Dana's Stenopora, ( Chcetetes) gracilis, especially 

 in the lobate bifurcation of the terminal branches ; but the 

 internal structure, so far as known to us, does not altogether 

 correspond with the latter. Our Stenopora disagrees with 

 Dana's species in the same way as S. ovata does ; viz. the 

 periodical thickenings, although faintly marked, are much too 

 numerous for S. gracilis. 



Locality and Horizon. In a fine conglomerate containing 

 much chloritic matter, Gympie Gold-field. Devonian or Car- 

 boniferous (?). 



Collector. The late Richard Daintree, Esq., C.M.G., F.G.S. 

 (Coll. Brit. Mus.) 



Genus Ar^OPOKA, Nich. & Eth., Jun., gen. nov. 



Gen. char. Corallum massive, resembling that of Favosites, 

 of polygonal corallites, which radiate outwards from an ima- 



