108 



ever, may I think be placed with the pedunculate form, and that 

 of Notamia with the sessile or immersed variety. 



To show the extent in which organs either avicularian or 

 vibracular exist in the cheilostomatous Polyzoa, a list is subjoined 

 of those genera and species contained in the present Catalogue, 

 in which I have noticed the existence either of avicularia or vi- 

 bracula or of both : 



1. Species possessing avicularia. 

 Those marked with an asterisk * also have vibracula. 



1 . Alysidium 1 spec. 



? *2. Amastigia 1 



3. Bicellaria 2 



4. Bugula 5 



*5. Caberea 4 



6. Calpidium 1 



*7. Canda 2 



8. Carbasea 2 



9. Catenicella 17 



10. Cellepora 8 



11. Emma 2 



12. Eschara 11 



13. Flustra 5 



14. Lepralia 24 



15. Membranipora 10 , 



*16. Menipea 6 , 



1 7. Notamia 1 



18. Retepora 3 



19. Salicoraaria 4 



*20. Scrupocellaria 7 



116 



2. Species having vibracula only. 



1. Cupularia 5 



2. Lunulites 4 ,, 



3. Selenaria 1 



10 



from which it appears that of thirty-six genera, twenty include 

 species armed in the one way or other; and that of 191 species, 

 no less than 126 are furnished with avicularia or vibracula ; a 

 circumstance in itself sufficient to demonstrate the importance 

 of these organs in a systematic history of the Polyzoa. 



G. B. 



