EXPLANATION TO PLATE X. 



Km. 1. Tliiiini-iii il(tl'nii (Allnian). Bart of branch (enlarged). 



2. Tliiiiiirin ilijl'iixn. Two hydrotlircM' (greatly enlarged). 



3. Tliiiiiirin ilijl'iixn. Single hydrotheca (greatly enlarged). 

 4. Tliiiiiirin ilnlli Nutting. Part of branch (i-nlarfrcd). 



5. Tliiiiiirin ilnlli. Part of stein, showing liranrh origin (enlarged). 



6. Tliiiiiirin ilnlli. Two hyilrntlH'iw (greatly enlargfil). 



7. Thuiaria similw (Clark). Part of colony with gonangiuni (enlarged). 

 s. Tliiiiiirin ximi/ix. Hyilrutlu-cM 1 (greatly enlarged). 



!). Tliuinrin niinilix. Four hydrothec;c (greatly enlarged). 



188 



