160 BRITISH TUNICATA. 



1. Diazona hebridica (Forbes & G-oodsir) Alder.* 

 (Plate XLIX, figs 4-6.) 



[Diazona riolacea SAVIGNY in Descr. Egypt., Hist. Nat. I 



(1809), pt, 2, p. 23, and Mem. Anim. sans Vert. pt. 2 



(1816), pp. 35, 61, 116, 175, pi. ii, f. 3, and pi. xii; 



FLEMING in Edinb. Encycl. XIV (1820), p. 631; Philos. 



Zool. II (1822), p. 512 ; and Moll. Anim. (1837), p. 21.1 ; 



BICHVVALD Zool. Spec. 1 (1829), p. 269; DESHAYES Moll. 



in Cuvier's Regne Anim. (1836-1849), pi. cxxxii, f. 1 ; 



LECNIS Synops. Naturreicli, I, Zool. (1844), p. 412; 



RUPERT JONES in Cyclop. Anat. IV, pt, 40 (1850), pp. 1191, 



1197, f. 770; HOEYEN Handb. Zool. I (1856), p. 704; 



WOODWARD Man. Moll. (1856), p. 342, pi. xxiv, f. 13; 



OWEN in Encycl. Brit. ed. 8, XV (1858), p. 332; BRONN 



Thier-Reichs, III, 1 (1861), p. 117, pi. xii, f. 12, and 



pi. xiii, f. 13.] 

 [Diazoma mediterranea LAMARCK Hist. Nat. Anim. sans 



Vert. ed. 1, III (1816), p. 102; STARK Elem. Nat. Hist, 



II (1828), p. 120.] 

 [Polyclinum diazona CUVIER Regne Anim. ed. 1, iv (1817), 



pi. xi, f. 6; ed. 2, III (1830), pi. xiv, f. 6; and (transl.), 



Anim. Kingd. Ill (1837), pi. x, f. 6.] 

 [Diazona mediterranea Risso Hist. Nat. Europe merid. IV 



(1826), p. 277; DUJARDIN in Lamarck's Hist. Nat. Anim. 



sans Vert, ed. 2, III (1840), p. 499.] 

 Syntethys hebridicus FORBES & GOODSIR in Trans. Roy. Soc. 



Edinb. XX (1851) [pt. 2, p. 309, pi. ix. f. 4a] ; [FORBES in 



Brit. Assoc. Rep. for 1850 (1851), 'p. 242;] FORBES & 



HANLET Brit. Moll. IV (1853), p. 244; [WOODWARD Man. 



Moll. (1856), p. 340; H. & A. ADAMS Gen. Recent Moll. 



II (1858), pi. cxxxii, ff. 9, 9aj. 

 [Diazona helridica ALDER in Ansted's Channel Isl. (1862), 



p. 219 ; in Ann. Nat, Hist. (3) XI (1863), p. 169; and in 



Rep. Brit. Assoc. for 1866 (1867), p. 208.] 



Common l><txe massive, transparent, greenish white, 

 broadly cylindrical. Individuals rather slender. TJiorax 

 elongated, yellowish-green with a circular opaque 

 white line above, two similar longitudinal lines on the 

 ventral, and one on the dorsal aspect. Apertures 

 terminal, tubular, the branchial central, the atrial 



* [That this is Savigny's Diazona violacea there can now be no doubt.] 



