SERTULARIA OPERCULATA. 263 



cidedly rimmed, than in the preceding species. S. gracilis 

 has a wider range than S. pumila, and is not an exclu- 

 sively littoral form. 



Hob. Brighton, on algae (Hassall): Norfolk and Corn- 

 wall (" delicate var. of pumila") (C. W. P.): Swanage Bay, 

 Dorset, abundant on H. falcata &c. ; Lulworth, on stone ; 

 Ilfracombe (T. H.): Durham coast; Shetland (A. M. N.) , 



3. S. OPERCULATA, Liunasus. 



" SEA-HAIR," Ellis, Corall. S, t. iii. figs. 4, B. 



SERTULARIA OPERCULATA, Linn. Syst. 1307 ; Espcr, Pflanz. Sert. t. iv. figs. 1,2; 

 LamJc. An. 8. V. (2nd ed.) ii. 144; Johnst. B. Z. 77, pi. xiv. 

 figs. 2, 2. 



,, USNEOIDES, Pall. Elench. 132. 

 DYNAMENA OPERCULATA, Lainx. Cor. flex. 176. 



PULCHELLA, D' Orbigny. 

 AMPHISBETIA OPERCULATA, Agassis, N. H. U. S. iv. 355. 



Plate LIY. 



SHOOTS long, very slender, filiform, slightly jlexuous, branch- 

 ed ; the branches alternate, dichotomous, often much ra- 

 mified, erect; HYDROTHEC^E opposite, small, somewhat 

 obconic, the aperture sloping inwards towards the stem, 

 its outer angle produced into a very fine and sharp point, 

 which is slightly incurved, and with a minute denticula- 

 tion on each side ; GONOTHECJE obovate, smooth, with a 

 plain circular aperture. 



ELLIS'S name for this species, "the Sea-hair Coralline," is 

 sufficiently expressive of its slender, wavy habit. It 

 grows in tufts, several inches high, many shoots rising 

 together and giving off long, ramified branches, so as to 

 form very large tangled masses. The branches are dicho- 

 tomous and decidedly erect, and in each axil there is an 

 inconspicuous calycle. The hydrothecae are minute, and 

 with their acute projecting points give a decidedly serru- 

 late appearance to the stems and branches. Of the lateral 



