branches vary in degree of separation. Corallites up 

 to 30 mm long, i2-i5 mm wide and about io mm deep. 

 Walls sharply ridged, about 2 mm thick. Septa with 

 many irregular teeth, thinner than !M. brasiliensis, 

 about 12- i 4 per cm, about six principal, up to i.5 mm 

 exsert. Columella of twisted septal trabeculae, well 

 developed, 2 to 2.5 mm wide. Costae traverse greater 

 length of corallites with slender teeth directed upwards. 



46. !Mussa angulosa (Pallas), (Plates 34, 35). 



Also J\4ussa lacera (Pallas) Oken, (Verrill 1902). 



Described by Matthai (1928), pages 204-208. 



Heavy short branches ending in cups up to 12 cm 

 long and 4.5 wide. Walls 6-8 mm thick. Septa have 

 strong teeth pointing obliquely upwards. Toothed 

 ridges continuous with the costae run lengthwise down 

 branches. Found in the Bahamas and the West Indies, 

 more rarely off the Florida Keys. 



Branches divergent, heavy, large, calices forming 

 convex upper surface. Valleys often constricted be- 

 tween columellar centers. lAp io i2 cm long and 4.5 

 cm wide, down to 2 cm width between centers. Walls 

 6-8 mm thick, often angular. Septa 8 per cm, four or 

 five principals sloping to meet columella. Septal mar- 

 gins with about 9 large blunt teeth, directed oblicjuely 

 upwards, upper ones 4 mm long and 3 mm wide at 

 base, sides spinulose. Septa exsert up to 6 mm, with 

 two teeth on exsert portion. Columella well developed, 

 centers 4-5 mm in width, made of thin interlaced tra- 

 beculae. Costae continuous with septa extending down 

 wall, with upwards directed teeth. 



47. Jsophyllastrea rigida (Dana), (Plate 36). 



Also ^uss^ (Symphyllia) rigida (Dana), (Verrill 

 1902). 



96 



