Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/345

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important group of shells. A fourth genus is represented by some very curious Strophomena-like shells, belonging to a group formerly placed by Dr. Deslongchamps under Argyope, but subsequently removed by him to the Terebratulidae. The three French species, A. liasiana, A. Perrieri, and A. Suessii, I have found in England in the Lias, as also a minute shell, the Spirifera oolitica, mihi, which will have to be arranged with them. The peculiar form of these shells, their long hinge-lines, compressed valves, and finely folded or plicated exteriors, even in ignorance of the internal form of the loop, are, I think, sufficient to justify their arrangement eventually under a new genus or subgenus. I have two species from Wolumbilla, A. punctata and A. wollumbillaensis.

All the above Brachiopods occur together in the blocks which yield Purisiphonia.

Lamellibranchiata. — The importance of this class in connexion with the palaeontology of Queensland is indicated by the fact that the collection includes 22 genera and 36 species ; and there are fragmentary evidences of others that would still increase the list. Of this group the Aviculidae are the most frequent, of which there are eight or nine species. One of these is the A. braamburiensis, Phil., of our Oxford Clay, the only shell in this class which can be satisfactorily identified with a European species. Most of the other Aviculidae from Queensland have a reticulated ornamentation, and evidently belong to the group of which the above shell may be considered a type. Species of Lima and Pecten are also abundant, one species of the latter genus approaching the P. retiferus of the Great Oolite, whilst another is not unlike P. rigidus of the same formation. Cythereoe, equalling in size any of the Tertiary species, appear also to have been abundant ; the most noteworthy of the other genera are Thracia, Panopoea, Mya, and Trigonia, to which allusion has already been made.

Gasteropoda. — Seven genera, including ten species, occur in Queensland, the prevailing shell being Natica variabilis. The others are generally represented by solitary examples, the worn state of some of which prevents specific comparisons.

Cephalopoda. — No trace of any Ammonites, which are so abundant in the Western Australian beds, appears in the collection from Queensland. The specimen, the inner whorls of which were referred to that genus, is a gigantic Crioceras, which exceeds in size any specimen I have ever seen from Neocomian strata, wherein that genus attains its largest dimensions. This specimen is in a dark- blue limestone matrix, and the portions preserved retain their test ; but unfortunately, except a crushed Rhynchonella, there are no other remains associated with it to assist us in arriving at its precise geological age.

The only other genus is Belemnites. Examples of this occur under three conditions : — 1st, as detached frusta, as much water-worn as if they had come from Postpliocene gravels ; 2ndly, in blocks having a sandy matrix, containing small pebbles, coloured by manganese (here, again, they were very much broken or abraded before they were