1867.] MESSRS. ADAMS AND ANGAS ON A NEW LAND-SHELL. 907 



stouter than those of Hyalonema. No tentacles of the Zoanthus 

 could be detected, the skin of the polype and the motive organs only 

 remaining within the polypidom in a favourable condition for obser- 

 vation. 



4. Description of a New Species of Land-shell belonging to 

 the Genus Coeliaxis, H. Ad. and Angas. By H. Adams, 

 F.L.S., and G. F. Angas, F.L.S., C.M.Z.S. 



(Plate XLIII.) 



In a paper read at the Meeting of the Society on the 10th January, 

 1865, vFe gave a description of a nev? species of Land-shell from the 

 Cape of Good Hope, for which the subgeneric name Coeliaxis was 

 proposed. Adult specimens of a second species, possessing a con- 

 tinuous peritreme and distinct parietal plate, have since been re- 

 ceived by us from the Solomon archipelago, from which it would 

 appear that Coeliaxis must be considered a distinct genus, having 

 more affinity with Gibbulina and Ennea than with Suhulina, to 

 which we at the time referred it. Of the species upon which Coeliaxis 

 was founded, only two examples, in the British Museum Collection, 

 have the apertures at all complete. In one of these there is no trace 

 of any parietal plate ; while in the other, which is rather more ma- 

 ture, a callosity or tubercle, considered at the time accidental, exists, 

 thus rendering it probable that in quite mature examples of this 

 species the parietal plate will also be found distinctly developed, and 

 the peritreme of the aperture continuous. 



Genus Cceliaxis, nob. (char, emend.). 



Testa umhilicata, turrita, oblique costulata ; spira plerumque 

 decollata; apei'tura jilica parietali vel tuberculo munita; perist. 

 continuum, simplex, rectum. 



Cceliaxis exigua, nob. (PI. XLIII. figs. 16, 17, p. 890.) 



C. testa anguste et profunde umbilicata, cylindraceo-turrita, 

 tenui, oblique costulato-striata, pallide fulva ; spira decol- 

 lata, supenie attenuata ; anfr. superst. 1 1, subplanatis, ultimo 

 costa hasali sidcum interiorem angustum formante ; aper- 

 tura subverticali, rhomboidea, plica parietali spirali in medio 

 posit a ; perist. simplici, continuo, soliito, margins columellari 

 expanse. 



Long. 17 mill., diam. 4 mill., ap. 4 mill, longa. 



Hab. Solomon archipelago. 



