152 WALTER GARSTANG, M.A. 



Form j3. — Dejpressa. Attached as described above; 

 littoral. 



Channel Isles (=A. rubrotincta and 

 A. robusta, Hancock). 



Var. 3.— Flava. Body-walls yellowish, with little or no trace of red; 

 tentacles rarely exceeding 40 in number. 



Form a. — Erecta. As above ; infra-littoral. 



Adriatic. [West coast of Scotland 

 (= A. lata, Herdman ; but the colour of 

 this race is only known from spirit 

 specimens).] 



Form (3. — Depressa. As above ; littoral. 

 Isle of Wight. 



DESCRIPTION OF PLATES V. and VI., 



Illustrating Mr. W. Garstang's paper " On some Ascidians from the 

 Isle of Wight." 



N.B. — All the figures were drawn from preserved material. 



PLATE V. 



Fig. 1. — Ascidia mollis, Aid. and Hanc. The largest normal individual, 

 nat. size. 



Fig. 2, — A. mollis. Culs-de-sac of the test vessels, magnified. 



Fig. 3. — A. mollis. Another individual of smaller size, as seen after removal 

 of the test ; twice the natural size. 



a. = View of the right side, showing the musculature. 



b. = View of the left side, showing the disposition of stomach and 



intestine. 



Fig. 4. A. mollis. Portion of the pharyngeal wall of the same individual; 

 much enlarged. Zeiss, Obj. A. Oc. 2, Cam. luc. The dark portions represent 

 the longitudinal furrows, the light portions the elevations which are caused 

 by the " minute plication " of the wall. 



c.d. = Connecting ducts between the horizontal and the internal longi- 

 tudinal vessels. 



h.v. — Horizontal vessels, forming three complete series and a rudimentary 



fourth. 

 i.l.b.= Internal longitudinal bars or vessels. 

 i.p. = Intermediate papillae. 

 p. = Papilla? on the int. long, bars above the connecting ducts. 



