22 ZOOPHYTES. 



Circulation. — A subject of much interest might admit of some discus- 

 sion, — ^namely, does any vital fluid, resembling the blood which circulates 

 throughout the system in the higher order of animals, perform a corres- 

 ponding function in this race of Zoophytes ? 



Here I acknowledge my observations have not been conclusive. 

 Some authors affirm that they have witnessed currents ascending and de- 

 scendinsf the stem of the Tubularia indivisa. On no occasion have I been 

 alike fortunate. I have subjected all different specimens, ages, and parts 

 to the microscope ; — all different views and positions have been chosen ; 

 yet I was uniformly unsuccessful. Nascent specimens, still of the palest 

 grey, almost white, which were more manageable than adults, never af- 

 forded any evidence of the fact. 



Nevertheless, let not these remarks be held as an imputation on the 

 accuracy or on the veracity of other naturalists, though I have no reason 

 to believe their vision more acute, or their instruments more perfect than 



mine. 



Extraordinary embarassment always accompanies the diminution of 

 light, from the use of such powerful magnifiers as are necessary to bring 

 very minute objects into view. Thence, although present, they may be 

 concealed amidst the supervening obscuration. 



All that I can say, therefore, concentrates in my inability to discover 

 circulation in the Tubularia indivisa — reminding the reader that some ob- 

 servers of no mean note have denied facts advanced by naturalists from 

 the same cause, which later authorities confirm. One example may be 

 given in the cilia fringing the tentacula of certain zoophytes. 



Having thus briefly disposed of the course of the natural functions 

 uninterrupted, our attention may be now directed to the results of a few 

 experiments regarding the nature of this zoophyte, from which physiolo- 

 gists may possibly draw some deductions subsequently, although presently 

 appearing matters more of curiosity than use. From these we shall dis- 

 cover, in the first place, that superabundant organization may be probably 

 promoted artificially. 



Should an animal be seen slumbering in apparent death from priva- 

 tion of the heart, and if life, motion, and activity were to follow the resto- 



