LIFE-PROCESSES OF CORAL COLONY 113 



normal projections of dominant zooids scattered irregularly 

 over its surface ; but if sufficient damage be done to it to 

 destroy the apical zooid as well as a fair portion of its entire 

 length, then the remaining part will at once start budding 



Fig. 40. 



Fi&. 41. 



Type op Repair of Madrepora 

 WHEN THE " Dominant Apical 



ZOOID " is not DESTROYED. 



Process at the end of 100 days. 



Type of Repair of Madrepora when 

 THE "Dominant Apical Zooid" is 



ENTIRELY DESTROYED. 



Process at the end of 100 days. 



with vigour. The best examples of this mode of repair are 

 seen in those cases in which a colony is attacked by filamen- 

 tous algse. The thin green threads of this parasite enmesh 

 the branches, and penetrating into their substance, lead rapidly 

 and certainly to the death of the part attacked. Artificially 

 produced injuries also provide good examples of this mode of 

 repair. The first stage is noticed when, in contrast to the 

 dead terminal portion, the living part swells out ; its dominant 

 zooids become more conspicuous, and their projections increase 



H 



