4 



BRITISH FOSSILS. 



Hemipneiistes, to which genus I unite Toxasfer, is now for the 

 first time authentically represented by a British example, remark- 

 able for its novelty and for the light it throws upon the mutual 

 affinities of those genera of FcJiinoidea which have excentric mouths. 



The well known genus Ananchytes is combined (as indeed it 

 was formerly by Lamarck) with Holaster. In selecting the 

 common Ananchytes ovata of the Chalk for the subject of a plate 

 and description, I have been influenced by the necessity of clearing 

 up the confused synonymy of this fine fossil, and of settling the 

 numerous spurious species which have been constituted out of its 

 varieties, or from imperfect figures contained in old works. 



Gardiaster is a new genus, lately constituted by myself for some 

 remarkable and interesting sea-urchins, intermediate in their cha- 

 racters between Ananchytes and the true Spatangidcc. To the 

 account of the species figiu'ed I have added notices of all the forms 

 of this curious type which are known to me as British. 



Edward Forbes. 



October, 1852. 



