52 
opening into one another, surrounded by thick obtuse margins, which exhibit no traces 
of the original polygonal wall of the corallite. Mural pores few, very large, and 
irregularly placed. Tabulsc few and remote. {Nicholson and Mheridge fil.) 
Ohs. This species is unquestionably very closely allied to Pachpora cervicornis, 
De Blainv., of the European Devonian, and we have felt some hesitation in giving it a 
distinct specific designation. Both belong to that section of Favosiics in which the 
walls are thickened by the secondary deposition of sclerenchyma in successive laminse, 
the amount of this thickening being increased as the mouth is approached, and are 
therefore referable to Lindstrom’s genus Pachypora. Both are alike inform and general 
habits, and have singularly large, sparse, and irregular mural pores. After a comparison, 
however, of the Australian specimens with examples from the Eifel, macroscopically 
and microscopically, we have come to the conclusion that the former must, in the mean- 
while, be regai’ded as specifically distinct, upon the following grounds : — 
(ffl) Pachypora meridionalis (nobis), is, on the whole, a much smaller species 
than P. cervicornis, De Blainv., the branches in the latter often reaching 
8 or 10 lines in diameter. 
(h) The corallites in P. cervicornis can always be shown, by thin sections, to 
preserve their polygonal outline, in spite of the thickening to w^hich they 
are subjected ; in the axis of the branches they are regularly polygonal, 
and even the thickened lips of the calices show more or leas distinctly a 
polygonal line placed at a little distance from the mouth of the tube, 
which represents the original wall. On the other hand, in P. meridionalis 
the polygonal form of the corallites is more or less completely obliterated ; 
even in the axis of the branches the originally prismatic wall cannot be 
detected, and the thickened lips of the calices are simply rounded and obtuse, 
(c) In P. cervicornis the calices are about half-a-line in diameter, rounded or 
sub-polygonal, and only occasionally opening into one another. In P. 
meridionalis, on the contrary, the calices are mostly only about a third of a 
line in diameter (counting in, as before, the wall around them); their shape 
is very irregular, and they open into one another so frequently, and to such 
an extent, that they sometimes become almost vcrmiculate in character. 
Upon the whole, therefore, the present speeies is sufficiently distinct from 
P. cervicornis, De Blainv., to deserve a separate name, and we know of no other 
adequately characterised species with which it is necessary to compare it in detail. We 
may add that the differences between P. meridionalis and P. cervicornis, above alluded 
to, are much more conspicuous if we take specimens of the form usually known by the 
latter name in the Devonian Limestones of Devonshire, and figured as such by Milue- 
Edwards and Haime.* {Nicholson and Mheridge Jil.) 
Loc. Banning River, Burdekin Downs, and Arthur’s Creek, Burdekin Downs ; 
Regan’s, Northern Railway, thirty-one miles from Townsville. (12. L. Jack.) 
Genus — ALVFOLITES, Lamarck, 1801. 
(Emend. Nicholson, 1879.) 
Alveolites, Lamk., Syst. Anim. sans Vertiib., 1801. 
,, Nicholson, T.abulate Corals Pal. Period, 1879, pp. 117, 375. 
Sillingsia, De Kouinck, Poss. Pal. Nouv.-Galles du Snd, 1870, Pts. 1, 2, p. 75. 
Cladopora, Rominger, Report Geol. Survey Michigan, 1876, iii., Pt. 2, p. 50. 
Ohs. The chaotic condition in which the genua Alveolites remained for many 
years has been commented on, and the genus made the subject of research by Prof. 
Mon. Brit. Dev. Corals, PI. xlviii., fig. 2. 
