ANTHOZOA 



147 



upright branches; P. furcata Lam. (Fig. 241), in which the branches 

 are slender, and P. divaricata Lesueur, in which the branches are quite 



A 



Fig. 241 Fig. 242 



Fig. 241 — Porites porites (Vaughan). Fig. 242 — OcuUna 

 diffusa (Vaughan). A, the entire colony; B, a single 

 cup, showing the septa. 



slender (6 mm. in diameter, or less) and spreading: West Indies and 

 Florida. 



P. astreoides Lam. Colony not branchinii', but more or less globose, 

 often with thick lobes: West Indies and Florida. 



Division 2. APOROSA. 

 Coral solid; cup with usually numerous septa (Fig. 242, B) : about 10 

 families. 



Key to the families of Aporosa here descnbed: 



Oi Mostly soHtary corals 1. Tukbinoliidae 



Oj Colonial corals. 



6i Zooids not contiguous 2. Oculinidab 



hi Zooids close together or confluent 3. Astreidae 



Family 1. TUKBINOLIIDAE. 



Mostly solitary corals, with numerous septa and without a true 

 theca, imbedded in the sand or attached to some object : about 50 genera 

 and several hundred species, of which the greater number are fossiL 



Flabellum Lesson. Coral solitary, flattened more or less, tapering 

 tovv^ards the base, which is attached in youth but may become detached 

 later: over 50 species. 



F. goodei Verrill. Height up to 80 mm.; greater diameter 12 cm., 

 lesser 43 mm.; color in life salmon with brown stripes; a very fragile 

 coral : Newfoundland to Florida, in 200 to 500 fathoms. 



Family 2. OCULINIDAE. 



Colony usually dendritic, with large zooids more or less widely sep- 

 arated from one another; coral compact with 12 to 48 distinct septa and 

 usually a columella: about 22 genera. 



OcULiNA Lamarck. Colony dendritic with spirally arranged zooids: 

 many species. 



