BY THE REV. J, E. TETaSON- WOODS, F.G.S., F.L.S., ETC. 109 



considerable quantity. There are places on tlie rocks just above 

 the tidal marks -wliere a basket can be filled in a few minutes by 

 sweeping one's band along the sui^face. They are packed quite 

 close together. I shall add a few remarks upon the genus and 

 species further on, but I may observe now that the habits of this 

 mollusc are entirely those of the LiUorina, which it almost 

 completely replaces in the tropics. It extends abundantly, to my 

 knowledge as far south as Moreton Bay. It reaches a larger 

 size than LiUorina ccendescens, of our coasts. It was my impression 

 at first that the Littorinas of our south coasts and of Tasmania 

 were not found within the tropics. But with a very careful search 

 I was able to discover here and there solitary examples of 

 LiUorina ccerulescens. When dwarfed in size, it was somewhat 

 rugged with lines of growth showing how slow was its progress, 

 and sometimes curiously mottled with brown. On the reefs it 

 was occasionally met with, but a much finer and more solid shell 

 with very little of the elegant bluish- white tint so common on all 

 the south coasts. This shell reaching its maximum of develop- 

 ment in South Tasmania, and as I believe with Deshayes and 

 others, identical with L. ccerulescens of the Mediterranean, andX. 

 mauritiana of the Cape, as far as Natal. I have paid some 

 attention to this little species, and have watched the effect of 

 climate upon it with interest. Just as we notice the old residents 

 of North Australia by their peculiar aspect, so we may notice the 

 old established LiUorina. It is evident that certain rocks do not 

 agree with it, and few are foimd to live within their limits, and 

 those only in a stunted, distorted condition. I was inclined to 

 think that LiUorina injramidata, Quoy, had entirely died out. 

 This is the pagoda-like perrywinkle, with the double line of 

 tubercles on the body whorl, and an elegant single row upon the 

 spine ; I soon found that I was mistaken. It is somewhat common 

 at Port Douglas, though I never saw it anywhere else, and it 

 never attains one-fourth the size of the Port Jackson specimens. 

 The distribution of this species is remarkable. In South 



