CCELENTERATA — CORALS 



137 



attempts at budding. Septa usually wanting ; tabulae numer- 

 ous and conspicuous. 







B 



Fig. 53. — The compound " Honej'-comb coral," Favosites Javosus Goldfuss, 

 abundant in the seas covering the eastern portion of North America during the 

 Niagara (Middle Silurian) time. A, top view of colony ; B, side view of a colony ; 

 upper portion, showing the exterior with the pores and the vertical striations; 

 the lower portion is a section showing the granular tabulae, c, corallite, — the 

 space occupied by a single individual polyp ; c' ., corallite with a convex tabula at 

 the surface, margined by the characteristic pits; po., pores (probably unsuccessful 

 attempts of the individuals to bud new individuals) ; tab., tabulae. Natural 

 size. (From Hall.) 



1. Sketch a group of five or six corallites, (a) top view, {b) side 

 view of two. Label corallites, tabulae, mural pores 



2. How did the colony increase in size? 



3. What may the mural pores indicate ? 



4. How were the tabulae formed? 



5. What is the significance of the name ? 



6. Was the living animal able to move ? 



Halysites (Fig. 54). Ordovician to Silurian. 



Coral compound, composed of long, laterally compressed 

 corallites, and covered by a peritheca. Septa absent or repre- 

 sented by spines ; tabulae numerous. Between each pair of 



