Joly— On a Peculiarity in Oldhamia antiqua and 0. radiata. 447 



from the Periwinkle locality. It is seen that it is not quite 

 a plane surface, but one which has developed somewhat con- 

 choidally. It is rough, too, and unlike the usual bedding sur- 

 face. Nevertheless the 0. antiqua branches over the ridges without 

 sensible loss of distinctness, and undeviated. This is not an un- 

 common case. The specimen in question shows the 0. antiqua 

 in relief, the 0. radiata depressed. The specimen has been placed 

 in the Science and Art Museum, Kildare-street. 



SCIEX. I'UOC. lt.D.S. — VOL. V. FT. VI. 2 11 



