Haddon and Shackleton — A Revision of the British Actinice. 649 



[Epizoanthus arenaceus (D. Cli.), (not British, Mediterranean). (Poly thoa (sir. s.) 

 arenacea. Andres, 1884, p. 308. Type var. Palythoa arenacea, Cams, 1884. 

 p. 75.) 



(PI. Lix., fig. 7; PL Lx., fig. 4.) 



Form. — Column cylindrical. Body- wall, thick and opaque, sometimes 

 transversely wrinkled, about 15 capitular ridges and 30 tentacles; coenenchyme 

 incrusting, with a tendency to form linear bands. 



Colour. — Dirty sand (in spirit). 



Dimensions. — Height, 7-12 mm. ; diam., 3'5— 4*5 mm. 



The above description is taken from specimens identified at the Naples 

 Zoological Station. It will be seen that E. arenaceus differs from E. couchii., 

 chiefly in the great thickness of its body-wall, which gives it a very characteristic 

 appearance (PI. lix., fig. 7). Our specimens were not well preserved, and we have 

 therefore some difiiculty in determining satisfactorily anatomical characters. The 

 mesogloeal sphincter muscle differs from that of E. couchii in the appearance of its 

 cavities, the muscle-fibres being arranged in a single row round the mesogloea, 

 leaving an empty space in the centre of the cavity (PL lx., fig. 4). The thickness 

 of the body-wall can be well seen in transverse sections. Nematocysts are 

 present in the ectoderm of the oesoohagus, and in the mesenterial filaments.] 



Epizoa th macintoshi, n. sp. 



(PL Lviii., fig. 29 ; PL lix., fig. 1.) 



Form. — Short, very stout, rigid column, incrusted with foraminifera which give 

 it a very characteristic, white, granular appearance. Upper surface of contracted 

 column with 18 radial ridges. Coenenchyme apparently linear, of same nature as 

 the wall of the column. 



Colour. — Grayish white. 



Dimensions. — (In spirit) one polyp, 7 mm. high by 6 mm. in diameter ; the 

 other, 5 mm. high by 4-5 mm. in diameter. 



Zoca%,— Shetlands (1871). 



A small colony of three specimens of this species was kindly handed over to us 

 by Dr. W. C. M'Intosh, F.R.S., Professor of Zoology at St. Andrews. One of these 

 we devoted to the microtome ; the remaining specimens are in Prof. M'Intosh's 

 collection. We are pleased to be able to associate such a well-marked species 

 with the distinguished Scottish Zoologist who has placed his collection of Actiniae 

 at our disposal. 



TRANS. EOT. DUB. SOC, N.S. VOL. IV., PART XII. 4Z 



