TuBULARiA. Z. HYDROIDA. 113 



On examining a few tubes under the microscope I perceived in one of 

 them, and only in one, a crowd of minute elliptical bodies which were 

 in active motion, running up the tube on one side, and down on the 

 other, but frequently crossing, nor was it uncommon to see one ac- 

 celerate its pace and beat the others in the race. The tube had lost 

 its head, and the moving bodies were evidently, as I think, infusory 

 animalcules which had got admission into it ; — the currents they 

 created are therefore to be distinguished from those observed by Mr 

 Lister, analogous to the circulation in the Tubularia and Sertula- 

 riadae. 



4. Tubularia,* Linnaeus. 

 Character. — Polypidom rooted, more or less plant-like, hor- 

 7iy,Jistular, simple or branched ; no cells — Polypes protruding at 

 the ends of the tubes or branchlets, non-retractile, the head crested 

 with one or two circles oftentacida. 



* Tubes undivided. 

 L T. iNDiviSA, tid)es clustered, simple, cylindrical, narrowed 

 and interwoven at the base : head of the polype crested with tivo 

 rows of tentacula. E. Lhwyd. f 



Plate IIL Fig. 1, 2. 

 Remarkable Sea-plant, Lhwyd m Phil. Trans, abridg. vi. 7.3, pi. .0, fig. 1. 



(pessima.) Adianti aurei minimi facie planta marina, Rail, Syu. 31, 



no. 4. Jussieu in Mem. Acad. Roy. des So. 1742, p. 296, tab. 10, fig. 



2. Tubular coralline like oaten pipes, Ellis in Phil. Trans, xlviii. 



tab. 17, fig. D. Ibid, abridg. x. 453, pi. 10, fig. D. Corall. 31, no. 



2. tab. 16, fig. C. Tubularia indivisa, Lin. Syst. 1301. Soland. 



Zooph. 31. Berk. Syn. i. 214. Turt. Gmel. iv. 666. Blumenb. Man. 

 272. Turt. Brit. Faun. 210. Steiu. Elem. ii. 437. Wern. Mem. i. 

 563. Lam. Anim. s. Vert. ii. 110. 2de edit. ii. 125. Lamour. Cor. 



* Formed from tuhulus — a little hollow pipe. 



t Edward Lhwyd or Lloyd (as Dillenius spells the name) was born in 1670 

 and died in July 1709. He was keeper of the Ashmolean Museum, Oxford, and 

 was distinguished among his contemporaries for knowledge in antiquities and 

 natural history. " He is indeed," writes Archdeacon Nicolson, afterwards 

 Bishop of Carlisle, and a very competent judge, " if I may judge of him, the 

 greatest man (at antiquities and natural philosophy together) that I have had 

 the happiness to converse with." Letters to R. Thoreshy, F. R. S. v. i. p. 206. 

 Ray gratefully records his assistance in the Synopsis and Hist. Plantarum ; and 

 Petiver frequently mentions him as his " worthy," " curious," and " generous 

 friend." Of his life and writings the reader wall find an account in Pulteney's 

 Sketches of Botany in England, v. ii. p. 110-116 : and some additional particu- 

 lars in the " Analecta Scotica," especially in the Seco7id Series published at 

 Edinburgh during the present year. 



H 



