CYNTHIA EGHINATA. 97 



longitudinal. The exception alluded to is the G unfit in 

 villosa of Stimpson from Pnget Sound, in which we 

 have found the meshes transverse in the same manner 

 as in G. echinata. It also resembles this species a good 

 deal in other respects. The fibres of the test, how- 

 ever, are slightly branched and not stellate, and the 

 branchial folds are seven on each side. 



Ci/nthia echinata is a northern species, not uncommon 

 in the seas of Norway and Greenland. We have yet 

 no record of its occurrence in the South of England. 

 It is found in North America (Sars). 



Genus 7. STYELA (Savigny) MacLeay, 1825.* 



[Dist<nnus (pars) G-AERTNER in Pallas' Spic. Zool. I, fasc. 10 



(1774), p. 24.] 



[Ascidia (pars) PALLAS Spic. Zool. I, fasc. 10 (1774), p. 24.] 

 [Cynthia (pars) SAVIGNY in Descr. Egypt., Hist. Nat. I 



(1809), pt, 3, p. 39.] 

 Ci/nthix 8tyel% SAVIGNY Mem. Anim. sans Vert. pt. 2 



[1816], p. 154. 

 [Styela MACLEAY in Trans. Linn. Soc. Loncl. XIV (1825), 



p. 546.] 



Stycla MENKE [Synops. meth. Moll. (1830), p. 122] . 

 [Phallusia SCHACHT in Arch. f. Anat. 1851, p. 178.] 



Body sessile, attached or sometimes free. Test 

 coriaceous, generally rough and opaque, adhering to 

 the mantle throughout. Both apertures quadrate or 

 4-lobed. Branchial xae with only four folds 011 each 

 side, the meshes rectilinear. Tentacular filaments 

 simple, linear. Stomach and intestine on the right side 

 of the body. Reproductive organs variable, situated 

 on both sides. 



In the account of the anatomy of this genus we shall 

 rely principally on that of 8. tuberosa and S. mamillarix, 

 not only on account of their large size, but also because 

 they are good typical species. In these two forms the 

 test is very tough, opaque, and coriaceous. The surface 



* This genus appears in the authors' MS. as "Stycla (Savigny) Menke," 

 but, as stated in the footnote on p. 19 of Vol. I, this is an error for Styela. 



ii. 7 



