154 NEREIDS. 



I have also scarcely a doubt of this being the Nereis margaritacea 

 of Leach (Supp. Encycl. Brit. i. p. 451. pi. 26), but Dr. Leach's 

 character of the species is entirely generical ; and Savigny and M.- 

 Edwards and Audouin have particularly described a Nereis margari- 

 tacea, which is not the same with the one before us, but more nearly 

 related to N. pelagica. Neither has this any relation to the Nereis 

 margaritacea of the 'Annals/ vol. iii. p. 294, which belongs to a 

 different section of the genus. 



Obs. Very similar to the preceding, from which I can only distin- 

 guish it by the greater length of the dorsal cirrus. Sir J. G. Dalyell 

 says : — " Colour of the body universally orpiment orange-reddish ; a 

 darker longitudinal line, composed of so many short lines, one on 

 each segment down the back. Belly lighter. The whole surface is 

 finely iridescent, reflecting the prismatic colours, whence it may be 

 conjectured that this is the Nereis versicolor of uomenclators. I 

 have never seen any specimens, of many taken in Scotland, with a 

 tinge of green." 



(a) Scotland, Lieut. Thomas, R.N. 



{b) An Irish specimen? 



(e) Berwick Bay, Dr. Johnston. 



(d) No locality. 



(e) Wick, Caithness, C. W. Peach. 



4. N. cserulea, jaws with five obtuse denticulations ; tentacular cirri 

 rather long, the superior reaching to about the sixth segment ; 

 post-occipital segment once and a half as long as the second ; feet 

 with the lobes obUque, the dorsal largest and longest, with a 

 swollen base, and its cirrus reaching the apex ; upper setigerous 

 branch obsolete, the inferior oblong, prominent ; terminal piece of 

 the bristles smooth ; inferior cirrus inserted behind its lobe. 

 Length 3-4" ; breadth 3-4'". 



Nereis cserulea, Linn. Syst. 1086; 3Ius, Adolph. Freder. i. 93. Penn. 



Brit. Zool. iv. 47. pi. 25. f. 32, 33; and edit. 1812, iv. 93. pi. 27, 



fig. sup. Turt. Gmel. iv. 88 ; Brit. Faun. 135. Stew. Elem. i. 390. 

 Nereis raargarita, Montagu in Lin7i. Trans, vii. 82. Turt. Brit. Faun. 



135. Penn. Brit. Zool. edit. 1812, iv. 94. 

 Lycoris margaritacea, Savign. Syst. Annel. 33. Lam. An. s. Vert. v. 



312; 2ude e'dit. v. 550. Stark, Elem. ii. 139. 

 Nereis margaritacea, Leach in Supp. Encyclop. Brit. i. 451. pi. 26. 



Grube, Fam. Annel. 48. Audouin S)- M.-Edw. in Ann. des Sc. nat. 



xxviii. 277 ; and in Litt. de la France, ii. 195. Williams, Rep. Brit. 



Assoc. 1851, 187,211 & 231. 



Hab. The littoral region. 



Obs. The body is more compressed than any of the preceding 

 species, narrowed posteriorly, greenish or greyish-blue, iridescent, 

 with numerous equal narrow segments ; the ventral surface yellow- 

 ish-brown, as are also the feet, which project considerably. The 

 dorsal cirrus reaches the apex of the dorsal lobe, but does not project 

 beyond it. The anal segment is small, cylindrical, with long slender 



