38 Descriptions of New, or Little Known, Poly. 



zoa. 



approaches more to a typical Mesenteriioora ; but still the 

 gradation is so complete through the two species as to 

 show that, the zooecial characters being identical, and the 

 zoarial merging into each other, there can be no real generic 

 difference. 



EXPLANATION OF FIGURES. 



Plate I. 



Fig. 1. Gatenicella venusta. Fig. Ih. Back of same. 

 Fiof. 2. Gatenicella urnula. Fig. 2a. Back of same. 

 Fig. 8. Mucronella avicularis. 



Plate II. 



Fig. 1. Diastopora cristata, showing one surface of a lobe, 

 with the extension of the calcareous septum. Fig. la. 

 Another portion of the same specimen, showing an 

 encrusting part, a bilaminate lobe, and an ooecium. 



Fig. 2. Diastopora capitata, natural size. Fig. 2a. One of 

 the isolated lobes magnified. 



Fig. 3. Stomatopora geminata. 



The wrong scale has been placed with Plate II., the figures 

 of which are only magnified about half the extent of those 

 in Plate I. 



