The Actiniae of the Plate Collection. 299! 



The mesenteries are arranged on the macrotype, in one iiidi- 

 vidiial in sixteen and in another in fourteen and a half pairs, an 

 odd mesentery in the latter case occnrring on one side of the sulcar 

 directives and not on the other. In the lower part of the colnmn 

 the mesenteries project but slightly into the central cavity and their 

 mesogloea is throughout exceedingly thin and homogeneous in struc- 

 ture. Their longitudinal muscnlature is very feeble. No reproductive 

 Organs were observed. 



