128 Z. HYDROIDA. Sertularia. 



when dry, straig-ht, flattish, jointed, with a pair of opposite cells on 

 each interspace ; branches patent, mostly undivided, jointed like the 

 stem. Cells tubular, the upper portion free, erecto-patent, with an 

 even aperture often girded with two or three faint circular wrinkles. 

 Pallas says that the cells incline to one side of the stem, a character 

 which Dr Fleming- failed to observe, and which is not perceptible in 

 any of the specimens sent me by Dr Coldstream. " Ab eodem la- 

 tere," says Pallas, " ovaria in pinnis plerisque mediis crebra, in se- 

 riem conferta, minuta, obverse conica, supra trituberculata, et inter 

 tubercula osculo instructa." 



9. S. HiBERNiCA, " greater and lesser branches alternately pin- 

 nated ; denticles alternate, elliptical, ivith emarginate mouths ; 

 vesicles ovate, with a, denticulate mouth and transverse undidated 



stricB." 



Sertiilaria pinnata, Templeton in Mag. Nat. Hist, ix, 468. 



Hah. " Dredged up, with other marine productions, in the sound 

 of Donaghadee. Received from Mr J. Gilles, Aug. 1805," Tem- 

 pleton. 



" The branching of this species is somewhat peculiar, each of the 

 primary and secondary branches springing out at an angle of 40° or 

 50°. That part of the stem which bears the denticles is waved so 

 as to bear each denticle on the projecting part ; the denticles are el- 

 liptic, and the mouth of each apparently a little hollowed inwards, 

 perhaps arising from the extremity being fractured ; the vesicles are 

 ovate, with 4 or 5 blunt teeth surrounding the mouth, and divided 

 into 6 or 8 portions by annulated undulating lines. It might be 

 classed among the large and strong sertularias, the principal shoot 

 being of the thickness of a sparrow's quill at its base, and 4 in. or 

 5 in. long. The branches shoot forth from opposite sides, the whole 

 coralline thus assuming a flat form, to the extent of 4 in. or 5 in." 

 Templeton^ 



10. S. NIGRA, cells nearly opposite, small, ovate, appressed, with 



a scarcely everted aperture ; vesicles ovate or elliptical. — Pallas. 



Vignette, No. 13, page 119. 



Sertularianigra,Pa//. Elench.135. Turt. Gmel.iv.676. 5osc, Vers, iii. 106. 



Turt. Brit. Faun. 212. Jameson in Warn. Mem. i. 365. Corallina, 86. 



S. Lichenastrum, Lin. Syst. 1313. (exelus. syn.) Dynamcna 



nigra, Flem. Brit. Anim. 545 La D. noire, Blainv. Actinolog. 484. 



Hab. Lizard Point, Cornwall, Pallas. Coast of Aberdeenshire, 

 Robert Brovm. Scarborough from deep water, Mr Bean. Coast of 

 Northumberland at Dunstanborough Castle, Mr R. EmbJeton. 



