266 BEPOET— 1882. 



In Ms classical ' Monograph of the Fossil Polyzoa of the Crag' (1859), 

 Professor Busk very much simplifies the diagnosis of Haime, because, as 

 I think, the types of the ' Crag ' were more suitable for this purpose than 

 those of the Cretaceous or Oolitic periods. 



'■ Zoaritmi erect, cylindrical, undivided or branched ; surface even, 

 furnished with openings of two kinds : the larger representing the orifices 

 of the cells, and the smaller the ostioles of the interstitial canals or tubes.' 

 ' Crag Polyzoa,' p. 120. 



Since this was written species of recent Heteropora have been dis- 

 covered and described by A. W. Waters, E.G. S.,' from the neighbourhood 

 of Japan, and by Professor Busk from the neighbourhood of New Zealand,^ 

 and a critical study of these species has thrown some little light upon 

 particular structures in the Oolitic types. I fail, however, to detect, either 

 in the descriptions of the recent, or in my own investigations of the 

 ancient type, any evidence, or characters, that would be sufficient to 

 establish a link between Monticuli'pora and Heteropora, or, in other words, 

 between Tabulate Corals (which have intercellular ; openings like Hetero- 

 pora) and Polyzoa. Yet it is very strange that in the Mesozoic epoch we 

 should have well-developed types like Heteropora which we are content 

 to call Polyzoa, and yet be unable to associate them with Palteozoic species 

 having similar external characters. But it is so, and without seeking to 

 do violence to structural evidence we must wait for future light by simply 

 working and watching. 



Professor H. AUeyne Nicholson, F.L.S., in his two works on the 

 ' Structure and Affinities of the Tabulate Corals of the Palaeozoic Period,' 

 1879, p. 256 ; and in the ' Structure and Aflinities of the Genus Monti- 

 culipora,' 1881, p. 62, has gone into the whole question of the apparent 

 affinity of Heteropora and Monticulii^ora. As the whole of his remarks 

 are founded upon structural evidence I willingly refer the student to the 

 elaborate details furnished by the author. Generally I agree with Pro- 

 fessor Nicholson, but much yet remains to be done in the correlation of 

 the Mesozoic and Pateozoic types. 



To Mr. Walford, F.G.S., of Banbury, and Mr. F. G. Longe, F.G.S., 

 my thanks are due for help by suggestions and the loan or gift of speci- 

 mens.^ I also thank Mr.' Robert ^Etheridge, F.G.S., and Mr. Newton, 

 F.G.S., for allowing me to examine specimens in the School of Mines. 



The preceding list of the ranges of types may help the student of our 

 Jurassic Polyzoa, and many of the blanks in the columns may ultimately 

 be filled in. 



References to letters in the various columns : — H., Haime ; W., Wal- 

 ford ; M., Morris' Catalogue. In the last column the figures refer to the 

 figures at the tops of the columns. 



I shall be glad to receive from any student of British or Foreign 

 Fossil Polyzoa a list of species which are known to be present in their 

 own neighbourhood, for the purpose of compiling a complete list of species, 

 or as far as possible complete. 



' ' On the Occurrence of Recent Heteropora; Jour, of Rmj. Microscoi). Sue. 1879 

 (June). 



■- 'OnEecent Species of Ileteropora; Jour, of Linn. Sue. 'Zoology,' vol. xiv. (1879). 



