Dr. Johnston's Catalogue of Zoophytes. 255 



3. C. dichotoma, stem slender, filiform, wavy, branched, marked with annular joints . 



branches alternate, simple, sometimes compound, annular at their origins ; cells cam- 

 panulate, entire. — Sea-thread Coralline. 

 C. dichtoma, Lam. Hist. Nat. ii. 113 ; Flem. Brit. Anim. 548 ; Stark, Elem. ii. 441. 

 Sertularia dichotoma, Linn.; Soland. Zooph. 48 ; Turt. Linn. iv. 682 ; Turt. Br. Faun. 



215 ; Stew. Elem. ii. 446 ; Bosc, Vers, iii. 118 ; Hoggs Stockton, 33. 

 Laomedea dichotoma, Lamour. Corall. 91. 

 Sea-thread Coralline, Ellis, Corall. 21, t. xii. No. 18, a. 

 Hab. On old shells in deep water, frequent. 



Height 4 to 6 inches, smooth, blackish. The stem is zig-zag, and from each angle there 

 sprouts a branch, above which the stem is marked with four or five rings, and a similar 

 ringed joint is at the base of each branch. The cells are on annular shoots, and are fre- 

 quently wanting. The polypes are reddish. Ovarian vesicles ovate. 



4. C. geniculata, stem erect, zig-zag, simple or slightly branched ; cells on annular stalks 



from the joints, alternate, urceolate, with a contracted entire aperture : height 1 inch. 



Knotted Sea-thread Coralline. 

 C. geniculata, Flem. Brit. Anim. 548. 

 Sertularia geniculata, Linn. : Soland. Zooph. 49. ; Turt. Linn. iv. 682 ; Turt. Br. Faun. 



215; Stew. Elem. ii. 446; Lam. Hist. Nat. ii. 120; Bosc, Vers, iii. 117; Hogg's 



Stockton, 33. 

 Laomedea geniculata, Lamour. Corall. 91. 

 Knotted-thread Coralline, Ellis, Corall. 22, t. xii. No. 19, b. Phil. Trans, xlviii. 629, t. xxii. 



No. 1. 

 Hab. On the broad frond of Laminaria digitata, and on some other Fuci, common, the 

 shoots connected by slender, creeping, tubular threads. 



Ovarian vesicles large, tubular or vase-like, with a contracted tubulous mouth ; oviform 

 bodies arranged in a moniliform series, roundish, with a darker centre. 



I have seen this species stained of a rose-red colour, which it appeared to have derived 

 from a minute parasitical Fucus which infested its stalk and cells. 



5. C. volubilis, stem creeping, tortuous, wrinkled, not jointed ; cells campanulate with ser- 



rated margins, on long, slender, filiform annular stalks. Climbing Bell-coralline. 

 C. volubilis, Lam. Hist. Nat. ii. 1 13 ; Flem. Br. Anim. 548. 

 Sertularia volubilis, Linn.; Soland. Zooph. 51, tab. 4, fig. e.f. ; Turt. Linn. iv. 680 ; Turt. 



Br. Faun. 214 ; Stew. Elem. ii. 444 ; Bosc, Vers, iii. 112; Hogg's Stockton, 34. 

 Clytia volubilis, Lamour. Corall. 88. 

 Small-climbing Coralline with bell-shaped cups, Ellis, Corall. 24, tab. xxiv. No. 21, a. A. 



Phil. Trans, xlviii. 629. tab. xxii. No. 2. 

 Hab. Attached to and creeping on other Corallines, frequent. 



A minute species, and a beautiful object for the microscope. I have seen it investing 

 the antennae of a living crab (Lithodes spinosa), which then resembled a hairy brush. The 

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