274 ILYANTHID.E. 



period, and I had no opportunity of seeing their segmen- 

 tation. All were strongly ciliated, and therefore were 

 already larva?. They were oval in form, § millim. in 

 length. One end becomes concave, the other conical. 

 In the centre of the former an opening forms, through 

 which granules escape, and this becomes the mouth ; the 

 escape of the granules leaving the visceral cavity. Soon 

 around the mouth four minute tubercles bud, which become 

 tentacles ; then two other tubercles nearer the mouth form 

 lips ; meanwhile the body becomes smooth, and cylindro- 

 conical. 



" The young lived in this state ten or twelve days ; and 

 attained one or one and a half millimetre in length. The 

 body continued entirely ciliated, and was become very con- 

 tractile. They swam freely in the manner of a Medusa. 

 mouth downward, by means of elongations and shortenings 

 of the trunk, and by openings and closings of the ten- 

 tacles. Sometimes they would oscillate, or revolve on 

 themselves." 



Arachnactis. 

 Lloydii. Cyathophylliadse. 



[membranaceus.] 



Xerianthus (?) vermicularis (E. Forbes). 



Dr. Johnston, in his "Brit. Zooph." Ed. 2, p. 222; pi. 

 xxxviii. figs. 2 — 5, has described and figured, on the 

 authority of E. Forbes, under the name of Act. vermicu- 

 laris, what seems either the young of the preceding- 

 species, after it has become stationary, or else a near 

 ally to it. It is described as " 0& long," and the larger 



