28 • OF THE PRINCIPAL WORMS 



taenia, and an argument like this, not ^ct freed 

 from douht, presents to our modern naturalists a 

 vast field for consideration. 



§ IX. Some learned writers have pretended that 

 the taenia, like the Sertiilaria Czoophytes J ^rows 

 longer by means of tlie apposition of new rings. 

 This opinion however is proved to be unfounded, 

 and it may be affirmed with certainty, that the tae- 

 nia, like all other living beings, increases in length 

 and size by the addition of a homogeneous matter 

 received into its vicera and prepared or animalized 

 by them. The various parts of the taenia exist- 

 ing in miniature in the egg, begin to be developed 

 from their leaving the ovum and continue to grow till 

 they acquire their natural bigness. Block having 

 examined several small taeniae, with an excellent 

 microscope, discovered in them a prodigious num- 

 ber of very minute articulations, which could not 

 be seen by the naked eye. (38) 



§) X. The taenia is very tenacious of life. Coit- 

 ^ef(3i)) asserts, that they can live more than twelve 

 hours in boiling veal broth, and come out as brisk 

 and active as they went in. Dr. JPfl.r(40) caused 

 a taenia to simmer over a slow tire, and observed 

 that he died so soon as some common salt, muriate 

 of soda, was added. 



In general, these worms, like others, sustain a 

 very high degree of temperature bef(»re life is de- 

 stroyed ;(1? ) this is not much in favour of that per- 

 fection of the senses which some writers have as^ 

 cribed to them.(4£) 



