12 INVERTEBRATE ANIMALS. 



Group 33.— Sections LITHOPHYLLIACE^ CESPITOS^ 

 et SIMPLICES (Milne Edwards). Estimated num- 

 ber of species : recent, 30 ; British, ; fossil, 154. 

 From the Trias upwards. In genus Mussa (Oken), as in 

 Astrcea and Meandrina, the corals grow in hemispheres 

 attaining ten or twelve feet in diameter, adorning the 

 ocean bed with richly coloured cupolas. 



^ Examples of nearly all the recent genera. 



Group 34. — Sub-Family EUSMILIN^ (Milne Edwards) 

 and allies, h (intensive), (tixIkyj, a blade. The name 

 alludes to the well-shaped and prominent blades which 

 form the rays of the calices. Estimated number of 

 species : recent, 54 ; British, ; fossil, 248. Meso- 

 zoic and Kainozoic. 



Group 35. — Genus OCULINA (Lamarck) and aUies. 

 Estimated number of species : recent, 18 ; British, ; 

 fossil, 18. Chiefly Kainozoic. 



IT The group includes the White-Coral of the 

 Mediterranean, and some very interesting 

 species from Northern Seas. 



Group 36.— Family TURBINOLID^ and allies. Turbo, 

 a top. Solitary corals, more abundant in former periods 

 than at present. Many of the existing species were 

 unknown before the comparatively recent use of the 

 dredge in deep waters for scientific purposes. Estimated 

 number of species : recent, 47 ; British, 3 ; fossil, 134. 

 Mesozoic and Kainozoic. 



M TurhinoUa, British; presented by R. McAndrew; 



Caryojjhyllia, Flahellum, Sphenotrochus, &c. 

 Glass models of the polypes in their proper 

 colours. 



