TUBULARIA. 53 



coloured than peach blossom, decorated this latter specimen. All had fallen 

 on the third day — none whatever remained. 



Such specimens are dark and bushy, the hydras commonly pale, 

 sometimes almost white. Except in colour, I have been unable to discern 

 any difference between those ornamenting the larger specimens of this 

 Tubularia in thousands, and those of fine and florid red and yellow on small 

 specimens, where there are very few. But it must be kept in view, that, 

 as a hydra naturally belongs to every extremity, where the hydrse are 

 numerous there must be many parts ; where they are scanty, the specimen 

 being vigorous, the parts are few. 



Perhaps the dimensions of the Tubularia ramea in a salubrious situa- 

 tion much depends on age. Those specimens less mature have fewer 

 boughs, branches, and twigs, but the last always terminated by a hydra. 

 Though void of that surprising luxuriance above described, many are 

 extremely beautiful to behold. All the parts and proportions are of ad- 

 mirable symmetry ; the length of each twig being about double the expan- 

 sion of the hydra. — Plate X. The stem of such specimens is of dark 

 umber colour ; the hydra red and yellow. This, the hydra, which is the 

 organic part of the product, considered externally, consists of a single 

 row of 24 obtuse muricate teutacula, bordering the disc and around the 

 stomach, which rises as a central prominence of variable form.* This 

 pouch or stomach is sometimes flattened almost down to the disc on dis- 

 charging its contents. The hydra expands about a line between the oppo- 

 site tips of the tentacula ; therefore, it is smaller than that of either of the 

 preceding Tubularice, but its dimensions surpass those of any of the Scot- 

 ish SertularicB with which I am acquainted. — Plate Vlll.figs. 1, 2, enlarged. 

 The tentacula are endowed with sensible action ; and the head always 

 expands and turns towards the direction whereby light is introduced ; 

 but it has no influence whatever over the twig or the stem by which it is 

 borne. Therefore the naturalist who is told oi flexible zoophytes must 

 beware of believing in their voluntary motions — that they bend sponta- 



* Muricate, resembling an assemblage of low jiyramiJs, with slight intermediate im- 

 pressions. 



