TUBULABIAE 



101 



tentacles on the hypostome. Gonosome: either a free or a sessile 

 medusa with 4 radiating canals and 4 rudimentary tentacles: about 7 

 genera. 



PENNARIA Oken. With the characters of the family: about 6 

 species. 



P. tiarella (Ayres) (Fig. 164). The bright pink hydroid colony 

 may be 15 cm. in height, and is attached to piles, rocks, or seaweed in 

 shallow water; medusoid buds on the side of the hydranth; medusa 



Fig. 164 



Fig. 165 



Fig. 164 Pennaria tiarella; a hydranth with a medusoid bud (Hargitt). Fig. 165 

 Pennaria tiarella; a male (A) and a female (B) medusa (Hargitt). 



(Fig. 165) an elongated bell about 2 mm. long with 4 rudimentary ten- 

 tacles; the medusa is free-swimming chiefly during midsummer, the 

 greater part of the year it is more or less sessile : common from Maine 

 to Florida. 



FAMILY 8. CORYMORPHIDAE. 



Trophosome: hydranths solitary and 

 of large size with a basal and several 

 distal whorls of filiform tentacles; me- 

 dusae produced just within the basal 

 tentacles. Gonosome: free medusae with 

 4 radial canals and 1 to 4 marginal ten- 

 tacles, one of which is longer than the 

 rest: several genera. 



1. CORYMORPHA Sars. Large soli- 

 tary polyps with a soft striated outer 

 surface and no well-defined perisarc, 

 rooted by filamentous processes : 5 species. 



C. pendula Agassiz (Fig. 166). 

 Polyp pendant, 3 to 10 cm. high and 

 bright pink; medusa bell-shaped with a projection at the apex, with 

 1 large and 1 to 3 rudimentary marginal tentacles; manubrium extends 



Fig. 166 CorymorpJia pendula 

 (Agassiz). 



