PLATE VIII. 



Figs. 1-3. — Heteroplon pluma. 

 Fig. 1. — Natural size. 



Fig. 2. — Portion of hydrocladium, magnified ; front view. 

 Fig. 3. — Portion of stem with hydrocladia ; lateral view. 



Figs. 4-7. — Dijilocheilus mirahilia. 



Fig. 4. — Natural size. 



Fig. 5. — Portion of stem with two hydrocladia, magnified ; showing front and back views 

 of hydrothecse. 



Fig. 6. — Internode of a hydrocladium with its hydrotheca ; half profile. 



Fig. 7. — Portion of hydrocladium consisting of two internodes, each with its hydrotheca ; 

 half profile. 



