CORAL-MAKING AUTINOID POLYPS. ie 
mouth has its own circle; and in tlie third, the separation has 
gone so far as to complete the circles and make two independ- 
ent polyps. This dividing one’s self in two, for the sake of an 
increase of population, is the process called spontaneous fis- 
sion or fissiparity. 
This mode of budding does not belong exclusively to coral 
polyps, for it has been observed among a few Actiniz. Grosse 
describes its occurrence in a British species, the Anthea cereus, 
in which it results in two distinct animals. He says “the 
fission begins at the margin of the disk, and gradually extends 
downward until the separation is complete, when each moiety 
soon closes and forms a perfect animal.” The same author al- 
ludes to the occurrence of double-disked individuals of the gen- 
era Actinoloba, and Actinia as illustrating the process without 
a separation of the spontaneously developed pair. 
_ This spontaneous fission is the common kind of budding 
in the large Astrzea tribe. 

ASTRAA PALLIDA, D. 
The preceding figure represents a species of living coral of 
the Astrea family, from the Feejees, the Astrea pallida D. 
