110 BRITISH TUNIOATA. 



when old ; smooth and silvery on the inner surface. 

 Mantle (PI. XXXIX, figs. 2 and 3) thin, white, slightly 

 sprinkled with brown. Tentacular filaments linear, 

 stout, blotched with brown. Branchial sac (PI. XLI, 

 fig. 4) with four folds on each side. Ovaries (PL XLI, 

 fig. 5) large and white, lining the mantle with trans- 

 verse cylindrical convolutions. 



Height upwards of an inch when extended; IreadtJt 

 half to three quarters of an inch. 



Hab. Deep water, usually on shells. 



ENGLAND. Cullercoats, Nor thumb. ; brought in on 

 the fishermen's lines (Alder [1848]). [Dogger Bank 

 (Alder, 1865). Falmouth, Cornwall (Cocks, 1849).] 



SCOTLAND. Shetland (Jeffreys). [Dourie Voe, Shet- 

 land, 1863 (Normnn, 1868).]' 



First record. Alder & Hancock, 1848; coll. Alder. 



St>/ela coriacea is a very contractile species, and in 

 its two states of extension and contraction might be 

 taken for different animals. The close-set, minute 

 tubercles of its surface distinguish it from most of its 

 congeners. These are rounded and not shagreened or 

 facetted as in S. granulata, and they can scarcely be 

 seen without a magnifier. Young specimens conse- 

 quently appear to be smooth, and are almost flat when 

 contracted. Old individuals, however, become much 



more rugose. 



7. Styela pomaria (Savigny). 



(PL XXXVII, fig. 5 ; PL XXXIX, fig. 4 ; PL XLII, 

 figs. 1-7; PL XL VIII, fig. 10; and fig. 64 in text.) 



Cynthia pomaria SAYIGXY [in Descr. Egypt., Hist. Nat. 1 

 (1809), pt. 3, p. 39, and] Mem. Anim. sans Vert. pt. 2 

 [1816], p. 156,, pi. ii, f. 1, and pi. vii, f. 2; LAMARCK 

 Hist. Nat. Anim. sans Vert. ed. 2 [1840], p. 531 ; [RUPERT 

 JONES in Cyclop. Anat. IV, pt. 40 (1850), p. 1199 ; BRONX 

 Thier-Reichs, III, 1 (1861), p. 104, etc., pi. xii, ff. 5, 6 ; 

 GRUBE in Abh. Schles. vaterl.-Cultur, 1868-69 (1869), 

 pp. 112, 125]. 



