PERONELLA ROSTRATA. 523 



radiating partitions extending nearly over half the lower floor from the edge 

 of the test in specimens of which the dimensions are given below. 



Feronella rostrata 



! Laganum rostratum Agass., 1841, Mori. Scut., p. 118, PI, XXV. 

 ! Peronella rostrata A. Ac, 1872, Rev. Ech., Pt. I. p. 149. 



The only authentic specimens of this species I have been able to examine 

 are in the Jardin des Plantes and the Ecole des Mines ; the material represent- 

 ing this species is too scanty to arrive at a definite solution of its affinities. 

 It is evidently a Peronella. The elongate form, the position of the anus, and 

 structure of the spines surrounding it, its conical outline seen in profile, the 

 thickness of the test, the comparatively greater size of the ambulacral 

 petals, and short ambulacral furrows, distinguish it apparently from its con- 

 gener, P. decagonalis ; but, as I have already suggested, it may prove to be 

 only the adult of Peronella orbicularis, which has, although all the specimens 

 of it examined are small, points of resemblance to the present species, such 

 as we may naturally expect to find between the old and young of species 

 in this genus. 



New Zealand ; Zanzibar. 



