122 PALEONTOLOGICAL EVIDENCE OF 
which is retained in the genus in spite of its having a 
lateral fasciole, but this does violence to the classification, to some 
extent. 
ac 
coast. The species is a variable one, the specimens at Port Jack- 
son are smaller, paler in colour, and with much more salient and 
conspicuous large spines, so that I think we may consider Pro- 
fessor Duncan’s species as perhaps a variety. It was found at 
= eee yea the Sherbrook River in W. Victoria, very far 
moved from the present habitat.  Monostychia Australis. is 
pr of the forms closely allied to the existing Arachnoides, of 
which two other species are described by Professor Duncan. T 
must b rdin. 
i 
o 
reproductive system and on the position of the periproct. With 
regard to this I may say that since seeing Professor Laube’s mono- 
graph ave examined forty or specimens of Arachnoides 
placenta from various localities. I find it a very variable species. 
The position of the periproct is the most uncertain feature. It is 
very infra-marginal and marginal. Psammechinus Woodsii, Laube, 
is said to be a form closely allied to our Echinus magellanicus, of 
which Agassiz states that he received two specimens from Austra- 
ato by m 
very considerably from £. sami Sana which is a com- 
mon living form on the east coast, especially at Port Jackson. 
Leiocidaris Australie is a representative of Dorocidaris papillata, 
which is of world-wide sar ose ng =a T am not aware that it 
ever been found in Australian 
Altogether the facies of our pitied: is somewhat recent, 
and in some respects related to past periods of the earth’s history. 
tion to the recent fauna, with only one or at most two exceptions, 
is to oo of remote localities in Australia and of much 
warmer 
I shall ave to deal more generally with the mollusea in treating 
of their alliances. asten in ee first lace to correct an erro- 
e 
that I myself have erin ec a new Cominella from the eee ea? 
* Proc. Linnean Soc., N. 8. Wales, Sept., 1877. 
uy 
= 2 meee 2 > 
Re RSW ge Bile. at a eR PIS ONE AN NPIS EAE Be Sa ET CRO RN a a REA rage ee PEE ORR ES ay ney. oR ORE Ce Dee OEE 
