114 
Z. HYDROIDA. 
Tubularia. 
Flex. 230. Corall. 100. Cuv. Reg. Anim. iii. 299. Bose, Vers, iii. 89, 
pi. 28, fig. 5. Flem. Brit. Anim. 552. Johnston in Trans. Newc. Soc. 
ii. 252. Dalyell in Edin. New Phil. Journ. xvii. 411 ; and xxi, 93; 
and in Rep. Brit. Assoc, an. 1834, 600. Lister in Phil. Trans, an. 1834, 
366, pi. 8, fig. 1 Tub. calamaris, Pall. Elench. 81 Tub. gigan- 
tea, Lamour. Soland. 17, tab. 68, fig. 5. Tub. gracilis? Harvey in 
Proc. Zool. Soc. no. 41, p. 54 La Tubulaire chalumeau, Blainv. 
Actinolog. 470. 
Hah. On shells and stones from deep water. Leith shore ; Ork- 
ney and Shetland Islands, Professor Jameson . Scarborough, Mr 
Pean. Coast off Dunstanborough Castle, Mr P. Embleton. Cul- 
lercoats, Northumberland, Mr J. Alder. Berwick Bay. 
The tubes are simple or sometimes divided once at the base, where 
they are twisted and flexuous, fistular, even, continuous or sometimes 
wrinkled at distant intervals with a few annulations, horn-coloured, 
from 6 to 12 inches in height', and about a line in diameter. Ellis’s 
comparison of them to u part of an oat-straw, with the joints cut off,” 
is very apt They are filled with a soft almost fluid reddish-pink pulp 
in organic connection with the Polypes, which project from the open 
ends of the tubes, and are not retractile within them. The body, or 
naked portion, of the polype forms a globular knob of a scarlet colour, 
produced above into a sort of proboscis encircled with a series of nu- 
merous short tentacula of the same colour. Around the base of this 
body there is another circle of much longer tentacula from 30 to 40 
in number ; and between their insertion and the body clusters of ovi- 
form gemmules are produced at certain seasons. The neck of the 
polype is greatly constricted ; and we find that the recent tube is 
marked with several longitudinal pale lines, placed at equal distances, 
and which are evidently caused by some structure of the interior pulp, 
for when empty the tubes exhibit no such appearance. What is their 
relation to the currents observed by Mr Lister? — As the animal be- 
comes weak when kept in a basin of sea- water, the head drops off, 
like a flower from its stalk ; and if it is immersed, even when most 
vivacious, in fresh-water, the pulp is expelled from the tubes until 
these are almost emptied. If this is effected by a contraction of the 
tube (and the phenomenon is not otherwise easily explained), does 
not this imply a degree of irritability in the polypidom inconsistent 
with the theory of its extravascular character ? 
I can find no characters either in the description or figure of Tub. 
gigantea which warrant its separation as a distinct species. The 
character of Lamouroux is : “ T. tubulis rectis, simplicissimis, ad 
basim attenuatis, gradatim dilatatis, deinde sequali crassitie, lsevibus 
nitidisque.” — Neither do I find in Mr Harvey’s description of his 
