2 A MONOGRAPH OF TIIK TERTIARY POLYZOA OK VICTORIA. 



last-mentioiiud iiapoi-.s Mr. Waters deals willi spcciineii.s t'ruiii various Victorian 

 and Soutli Australian deposits collected by Mr. Allen, Mr. Tenisou Woods, 

 Mr. Etheridgc, and Professor Tate. 



There ean be no doubt that when other dei^osits from which I have no specimens 

 are examined, tlie number will be very largely increased. Even of the deposits here 

 dealt with, the oulv ones of whicli anything like an exhaustive examination has been 

 made are those at Schnapi)er Point and Muddy Creek. 



The most marked leaiuie of the fossil species is their striking resemblance to 

 those of the existing fauna. This is shown not only in the number of identical 

 species, but also in the abundance of individuals of the same or closely allied forms. 

 Thus, of the Cheilostoniata, among the Catenicellida) which at the present time arc 

 almost exclusively confined tt) the Australian seas, we have no less than foi-ty 

 species ; and in this connection it is to be noted that the only species hitherto found 

 fb.ssil out of Australia are two recently recorded by j\Ir. Waters from North Italian 

 Deposits in the Vicentine, which are referred to the Upper Eocene. The Adeon;e 

 are largely represented and the Retepora; are abundant, as are also Caleschara 

 denticulata, Membranipora radicifera, Selenaria maculata, Steganoporella magnilabris, 

 Porina gracilis, Lekytho})ora hystrix and various other markedly Australian types. 

 The living Australian Cyclostomata do not present any special characteristics, and 

 there is nothing jjarticularly noteworthy among the fossils. Of the species not 

 peculiai-ly Australian which are identical with recent species, most are cosmopolitan, 

 as Membrani]ioia savartii, Thalamoporella rozieri, Cribrilina radiata, Microporella 

 ciliata and Licheno})ora radiata. 



The age of the deposits has been the sulyect of a good deal of discussion among 

 geologists. They are now generally referred to the Oligocene or early Miocene, but 

 some are considered l>y different authorities to belong to the Eocene. It is difficult, 

 however, to belie\e that any of them can be so old as the Eocene, at least considering 

 it to be comparable to that of Europe. So far as an opinion can be formed from an 

 examination of the Polyzoa, they are not of very different ages. 



The classification adopted is mainly that given in my catalogue of the Marine 

 I'olyzoa of ^'ictoria, published in the Proceedings of this Society for f88(j, with, 

 however, sonic modifications. 



The nomenclature is that in general use. The only innovation of any con.se- 

 quence I have made is the introduction of the term thyrostome {OvfM, arofj-a) for the 

 opening through which the tentacles and oral extremity of the jjolypide are 

 protruded. The terms orifice, oral aperture and mouth arc inaccurate and confusing, 

 and the proposed name will, I think, prove advantageous. 



