ANTHOZOA. 53 



m. Tubes not united by proliferations, sometimes angular //. 



//. Tubes with inner wall complete, septa smooth. 



XXIV. Diphyphyllum. 

 II. Tubes *with inner wall often incomplete, septa carinated. 



XXV. Craspedophyllum. 

 ***^Heads, expansions or branching stems of prismatic tubes closely crowded. 6f. 



6f. Corallites with well-developed septa n. 



n. With well-marked styliform pseudo-columella. 



XXVIII. Lithostrotion. 



n. Without columella mm, 



vim. Septa carinated 5- 



5. Head of numerous, comparatively small prismatic corallites. 



XVII. Acervularia. 



5. Head of a few large corallites 55- 



55. Corallites separated by definite walls. 



38. Heliophylhim confluens. 

 55. Corallites confluent, not separated by definite walls. 



XVIII. Phillipsasircea. 

 mm. Septa smooth 6. 



6. Corallites prismatic with expanding calices, 12 strong septa 



uniting in adjoining calices. Mural pores regular. 



XXXIX. Thecia. 

 6. Corallites slender prisms, 12 septa, numerous tabulae, no 



mural pores XXI. Columnaria. 



6. Corallites minute, 4 primary septa XLVII. Tetradium. 



6. Corallites prismatic, septa of 2 kinds, the longer extending 



to the center, no tabulae LII. Septastrcea. 



6. Corallites with central part of calyx elevated above periph- 

 eral part XIX. Pachyphyllum. 



6f Corallites with septa absent, or represented by low ridges or rows of 



spines 0. 



0. Corallites regular prisms, with numerous tabulae nn. 



nn. Septa in form of low ridges, with costae ; no mural pores. 



XXI. Colutnnaria. 

 nn. Septa represented by spines or absent, mural pores in definite 



rows XXXV. Favosites. 



nn. Septa represented by faint ridges ; tabulae convex upward ; 



mural pores irregularly scattered XXXVII. Michelinia. 



nn. Tubes opening obliquely, openings crescentic on one side, mural 



pores large, scattered XXXIX. Alveolites. 



0. Corallites prismatic, of varying size, tabulae few 00. 



00. Small hemispheric heads with basal epitheca. Mural pores 



irregularly scattered XXXVI. Pleurodictyum. 



0. Corallites contracting at regular intervals. Tabulae convex upward. 



Septa rows of spinules XXXVIII. Choriostegites. 



0. Corallites thick-walled, elongate conical, opening obliquely, mural 

 pores present, tabulae few. Commonly branching stems. 



XLI. Cladopora. 



*** Heads of superimposed strata or layers which are divided into depressed or 



elevated pentagonal areas, with septal ridges extending over them. Basal 



epithecae generally preserved XX. Slrombodes. 



