HYDROID ZOOPHYTES 



203 



Fig. 109. — Hydroids. — After Hincks. 



Tubularia. II. A. Piece of Sertularia. II. B. A fragment enlarged, 

 showing sessile hydrothecae (H.) on both sides of the twigs. III. A. 

 Plumularia. III. B. A fragment enlarged, showing hydrothecae IH.) 

 on one side of each twig, an axillary gonotheca (G.) and minute nemato- 

 phores. IV. A. Campanularian. IV. B. A fragment enlarged, showing 

 stalked hydrothecaB (H.), a gonotheca (G.) ; C, the ccenenchyma ; P., 

 the perisarc ; S., a stalk. 



