TUNICATES 171 



spangled with stars, outlined nsually in brighter color than the 

 general surface of the jelly-like mass. Careful examination shows 

 that each " star " is composed of a half dozen or more mouth open- 

 ings ranged around a central opening which serves as a common 

 vent. Water is drawn in through the mouth openings and dis- 

 charged through the vent together with waste products. The mi- 

 nute larvae are tadpole-like in appearance and swim toward the light. 

 Finally they become fastened by means of their slime to some solid 

 object, and if in a situation suitable for growth they develop into a 

 gelatinous expansion composed of numerous aggregated ascidians 

 all derived by a process of budding from the original larva. 



In common with Molgnln, this species often colonizes in the 

 tanks of the New York Aquarium, the larvae being pumped in with 

 the sea-water from the harbor. 



