31 

 TABLE 1. 



Characters in which the Tad-pole Larvae of A. pellucidum and A. constellatum 

 are Diverse, listed in Parallel Columns. 



Character 



Amaroucium pellucidum 



Amaroucium constellatum 



Size of tadpole 



1.50 to 1.74 mm. total 



length 

 0.48 to 0.54 mm. body 



length 

 0.21 to 0.23 mm. body 



depth 



2.25 mm. total length 

 0.74 to 0.78 mm. body 



length 

 0.36 to 0.44 mm. body 



depth 



Color 



Pale straw color. 



Pale to orange. Varies 

 directly with the color of 

 the parent colony. 



Test vesicles 



Differentiated at two 

 points at beginning of 

 metamorphosis. 



Differentiated at four 

 points before liberation 

 from the parent zooid. 



Epidermal tubes 



Eight in number, large, 

 conspicuously developed, 

 persistent in the primary 

 zooid. 



None present. 



Muscle cells of tail 



About 42 muscle cells pres- 

 ent, two series (dorsal 

 and ventral) each made 

 up of three longitudinal 

 rows of about seven cells 

 each. 



About 160 muscle cells pres- 

 ent; two series, each made 

 up of four longitudinal rows 

 of about twenty cells each. 



Duration of free- 

 swimming period 



30 minutes to 43^ hours 

 or longer. 



10 minutes to 100 minutes. 



Per cent which 

 undergo metamor- 

 phosis, (under lab- 

 oratory conditions) 



46 per cent to 86 per cent 

 (based upon observations 

 of four lots aggregating 

 857 tadpole larvae). 



100 per cent. 



