ASCIDIA MAMILLATA. 75 



Mini are partially buried amidst the cellular matter of 

 the intestine, but are mostly accumulated towards the 



V 



dorsal border. The minute twigs of the duct are 

 greatly enlarged in places, are irregularly tuberous 

 or nodose, and give off short caecal processes. There 

 is but one ovary, which lies concealed in the cellular 

 matter at the upper extremity of the intestinal loop ; 

 it is an elongated sac with the duct at first small, but 

 on passing through the loop of the intestine it is much 

 enlarged when it reaches the other side of the body. 



There can be little doubt that the Ascidia aracli- 

 uoitJcd of Forbes is identical with tht A. mamillata of 

 Cuvier. The rich supply of blood-vessels ramifying 

 through the test in this species, and rising towards 

 the surface in the smaller ramuli, give it that delicately 

 reticulated appearance which suggested to Professor 

 Forbes the name of arachnoidea. That distinguished 

 naturalist dredged it in the ^Egean, whence it appears 

 to range to the south and west of England, disappear- 

 ing farther north. 



2. Ascidia mentula Mailer. 



(PI. II ; III ; XVII, fig. 1 ; PI. XX, fig. 1 ; and figs. 

 5, 6, 10, 1], 12, and 14, in text.) 



Axc'idla meutnla MULLER Zool. Dan. Prod. [1776], p. 225, 

 no. 2724, and Zool. Danica, I [1788], p. 6, pi. viii, f. 1-4; 

 FABIUCIUS Fauna Groenl. [1780], p. 331 ; [MONTAGU Test. 

 Brit. II (1803), p. 532 ;] LAMARCK Anim. sans. Vert. ed. 1, 

 III [(1816), p. 125]; ed. 2, III [1840], p. 532; [STEWART 

 Elem. Nat. Hist, I (1817), p. 391 ; BRUGUIERE] Vers, 1 

 [1789], p. 145, pi. lxii,f. 2-4, in Encycl. Meth. ; [STARK 

 Elem. Nat, Hist. II (1828), p. 117;] DALYELL Eare Anim. 

 Scotland, II [1848], p. 146, pi. xxxvi, f. 6, and pi. xlvi ; 

 FORBES and HANLEY Brit. Moll. I [1848], p. 32, pi. C, f. 1 ; 

 [GAEUS Zool. Scilly Isles in Proc. Ashmol. Soc. II (1851), 

 p. 266; LANDSBOROUGH Excurs. Arraii (1852), p. 49; 

 THOMPSON Nat, Hist, Ireland, IV (1856), p. 359 ; NORMAN 

 in Zoologist, XV (1857), p. 5707: MERRIFIELD Nat. Hist, 

 Brighton (1860), p. 80 ; MC!NTOSH in 'Proc, E, Soc. Edinb. 

 V (1866), p. 605 ; ALDEEinRep.Brit.Assoc. 1866 (1867), 

 p. 207; NORMAN in Eep. Brit, Assoc, 1868 (1869), p. 302]. 



