\\UNELLAFUSCA. 527 



AVENELLA FU8CA, Dalyell. 

 Plate LXXVII. figs. 6, 7. 



LA FUSCA, Dalyell, Rem. An. ii. 65 ; i. pi. xii. fig. 11. (Not Farrella 

 flisca, Busk, Q. J. Micr. Sc., nor Avenella fiisca, Alder, 

 Northumb. Cat., nor Valkeria fusca, Smitt, loc. cit. 502, 

 pi. liiL fig. 38.) 



AVENELLA DALYELLII, Wyville Thomson, Ann. N. H. ser. 2, ix. (1852), 403, 

 pi. xvi. B. 



Stem very much attenuated, " much matted and inter- 

 woven." Zooecia large (about -^ inch long), set at ir- 

 regular intervals, and not in the same line, more or less 

 curved, roughened with scattered horny bristles, of a 

 brown colour. 



Polypide with 20-24 tentacles. 



A. FUSCA is remarkable for luxuriant growth, and forms 

 " dense tangled masses." Its cells, according to Sir W. 

 Thomson, are not unlike the ergot of rye. 



HABITAT. On Sertularian hydroids, chiefly from rather 

 deep water. 



LOCALITIES. Scotland, on zoophytes, "or on sluggish 

 animals," e. g. Hyas araneus (Dalyell) : Newhaven, 

 amongst rejectamenta of the oyster-dredges, on various 

 species of Halecium and other corallines ; off Port Appin, 

 Argyllshire, on Diphasia pinaster ; Dogger bank (Sir 

 Wyville Thomson) . 



