6336
While members of the Thaliacea and Larvacea ( Appendicularia ) swim freely like plankton , sea squirts are sessile animals after their larval phase : they then remain firmly attached to their substratum , such as rocks and shells .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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