HYDROIDS. 



249 



the untrained eye might well mistake the fact that 

 they are animals. But naturalists have shown that 

 these plantlike forms produce Medusse buds, which 

 expand into genuine Medusa;, or Jellyfishes. Figure 

 478 shows a little cluster of Hydroids attached to sea- 

 weed, and Figure 479 shows a single individual of the 

 same very much magnified, with two of the buds much 

 enlarged, and a third quite prominent. Soon each bud 

 bccTmes detached, and floats away as a free Jellyfish, 



Fig. 482. — Tiaropsis. Northeast 

 coast of North America. 



Fig. 483. — Campanularian. The Hydromedu- 

 Sfe in the bell-shaped cups drop out and be- 

 come free Medusae, similar to Figure 482. 



Fig. 481. — Tubularia. 

 Massachusetts Baj-. 



?«, medusa;; r/, coronal ten- 

 tacle; /, proboscis. 



like Figure 480, and is then known as Coryne, or, as 

 it was formerly called, Sarsia, so named from Sars, a 



