290 



ERNEST WARREN. 



Diameter about 0'17 mm., and thickness of perisarc 15'1 fx ; 

 these dimensions are somewhat smaller in the dwarf variety. 



Hydranth. — The perisarc of the hydrocaulus is not 

 swollen into a loose sheath at the base of the polyp. The 

 number of tentacles in the large variety varies from 20-30, 

 and in the dwarf variety from 10-18. 



The average length of the polyp in the large variety is 



Text-fig. 4. 



Coryue piisilla Gartner. A. Large form x 15. B. Small 

 form X 15. 



I'ol mm., and breadth 0'363 mm., in the small variety 0"80 

 mm. and 0*22 mm. respectively. The diameters of the 

 capitula of the tentacles are about 0*13 mm. and O'lO mm. in 

 the two forms. 



The nematocysts in the capitula are of tAvo sizes : the large 

 measure 16'7 fi in length and 11*2 /x in breadth; the small, 

 8"9 jx and 5"3 fx respectively. The sizes of the nematocysts in 

 the two varieties apjDcar to be about the same. 



