OF NEW SOUTH WALES. 173 



Family Spatangiue. Agassiz, 1836. 



Urchins with plastrons limited by bare ambulacral avenues. 

 The posterior ambulacra, frequently divided by a fasciole, with a 

 sub-anal plaston. Other fascioles variously present. 



Genus 1. — Maretia, Gray, 1855. 



Test thin, flattened, large tubercles upon the I. areas, except 

 the odd one. Actinal plastron smooth, without spines. Only an 

 indistinct anal fasciole. Petals long, spreading, anterior groove 

 indistinct. Only one living species known. 



MaeetiA planulata, Leske, which was found by the " Chevert " 

 Expedition at Cape Grenville and Darnley Island. I have also 

 seen specimens from New Caledonia ; and it is rather 

 common in Port Jackson. The Australian species are 

 smaller and of light straw color, the spines much longer, and 

 more prominent than the New Caledonian species. 



Genus 2. — Eupatagus, Agassiz, 1847. 



Test thin, depressed, elliptical, petals arched, not sunk. I. areas 

 covered by large tubercles, crenulate, and perforate, circumscribed 

 by an elliptical peripetalous fasciole, a sub-anal fasciole present, 

 no anterior groove, and no tubercles in odd I. space. 



Eupatagus valenciennesii, Agas. The only living species 

 known, and which is found occasionally on the E. coast in deep 

 water. I have seen a specimen from Bass' Straits, and the 

 " Chevert " Expedition obtained it at Cape Grenville. 



Genus 3. — Lovenia, Desor, 1847. 



Ambulacral petals somewhat triangular, adjoining zones 

 forming crescents on each side of apex. Large tubercles, with 

 deep scrobicular circle on upper side, but not on posterior I. 

 space. Internal and sub-anal fascioles. There is only one living 

 species in Australia. 



Lovenia elongata, Gray, 1854. Distinguished by the deep 

 funnel-shaped cavity, in which anal opening is placed. Tropical 

 Australia, but sometimes found at Port Jackson. 



