61 
Upper Silurian rocks (probably Ludlow or Wenlock) of New South Wales, at 
G whilst the supposed Devonian of the same colony has yielded H. porosa, 
pl° same species has been shown by Prof. Nicholson and the Writer to occur 
^ in the Devonian Limestones of North Queensland, accompanied by three 
cat^l interesting forms — viz., ILelioUtes Dainireei, U. pJasmoporoides, and an indi- 
of tP ®Pncies which is now named Ileliolites Nichohoni. The most aberrant species 
G genus is H. plasmoporoides, Eth.fll. and Nich., which nearly approaches the genus 
(ismopora, by its comparatively irregular and few interstitial tubes. 
Heliolites pobosa, Goldfuss, PI. 1, fig. 6. 
porosa, Goldfuss, Petrefacta Germani®, 1820, i., p. 61, t. 21, f. 7. 
‘‘oiites porosa, M. -Edwards and Haimo, Polyp. Foss. Terr. Pal., 1851, p. 218. 
>> ,, M.-Edward.s and Haitne, Mon. Brit. Foss. Corals, 1853, Pt. 4, p. 212, t. 47, f. 1 a/. 
” ,, De Kouinck, Foss. Pal. Nouv.-Galles du Sud, 1876, I’ts. 1, 2, p. 81. 
” .1 Nicliokon and Eth. fil., Ann. and Mag. Nat. Hist., 1879, iv., p. 223. 
a s ■ Under this name we have assembled from localities in North Queensland 
specimens varying more or less slightly in their characters amongst them- 
cor ^1 ' which we think are all referable to Ileliolites 2 }orosa, Goldf . The composite 
faint! these corals is massive, with a flat under surface or base, having few and 
gq if concentric ridges. The calicos in all the specimens are circular, pretty 
Py c ^ ^®''^®foped in the same individual, and separated by unequal interspaces occupied 
of tubes | ; each calico varies from i to f line in diameter. The tubes 
iate ° *^®“onchyma are rather small and polygonal, and constitute somewhat large 
®P^es between the corallites. The septa are only visible here and there. 
Upon comparing a series of specimens of IT. porosa from German and British 
the considerable variation takes place — 1st, in the diameter of 
the rocks, we find that considerable variation takes place- , 
coenenchymal tubuli ; 3rd, in the 
®opta^ ^ hrtercalicular space occupied by the latter ; and 4th, in the length of the 
Udwa 1 variations are, indeed, shown in the figures given by ]\IM. Milne- 
^Ppear t ^® ®'^® ^f*^® f'® jo'fS®) ff'® Queensland examples 
ccejj ^ ° occupy a median place in the above scale ; the diameter of the corallites and 
Oq ^ yoial tubuli is greater than in some European examples and less than in others. 
lanfl ^ ^f'ole the interspaces occupied by the tubuli are perhaps greater in the Queens- 
oxamples. 
®dwar/^ vertical sections we can distinguish with ease the tabulse, as described by 
o®nen f Haime, horizontal, but sometimes oblique. These authors describe the 
®otne o^f f®f*uli as “ nearly regularly hexagonal.” Certainly this is the case with 
ffie en tubes on various parts of the Queensland specimens ; but we find by far 
u^ouer form is the polygonal. 
I'anT„-.,..°T^'. Uroken Eiver, a tributary of the Clarke River (The late B. Baintree) ; 
T?* xvi-vci, u ui tiitj v-zitimt/ xviver \^j.n(i kilo uyiLiu 
River, Burdekin Downs ; Arthur’s Creek, Burdekin Downs (B. I. JacTc) 
Uelioeites Daintbeei, Etheridge Jil. and Nicholson, PI. 1, figs. 7, 8. 
Daintrcci, Nicholson and Eth. fil., Ann. and Mag. Nat. Hist., 1879, iv., p. 224, t. 14, £. 3 a, h. 
convej.^' Gorallum compound, discoid or flattened; upper surface a little 
~__^^j ^^®de r surface more or less flattened, concentrically wrinkled round the edges. 
p^gj^^’^°U''--Ga'llcs du Sud, 1876, Ft. i., pp. 24, 25. 
*' '^®nenohv*"^'i following descriptions of species of Heliolites the terms “ coenenchyma” and 
Inhere jg fuhes” are used simply in accordance with pirevious custom, and for the sake of convenience. 
tubes” arn°r course, no true “ coenenchyma” in Heliolites and its allies, and the so-called 
®ully a specialised series of small corallite.s. 
‘ coenenchymal 
