238 ILYANTHID^E. 



eleven A.M. only about an inch in length of the fore parts 

 remained above the level of the sand, when it expanded, 

 and seemed satisfied. At night, however, it came out of 

 its burrow, and remained wallowing on the surface ; and 

 for a week after this it continued to go in and out once or 

 twice a day, grovelling and stretching awhile, and then 

 burrowing comfortably almost to the tentacles. 



This individual still survives in the same vase, after 

 six months' captivity ; it frequently remains for days 

 completely hidden, sometimes shows only the tips of the 

 expanded tentacles, and rarely more than the disk, above 

 the sand. It is perfectly domiciliated. 



Another of the individuals referred to gave birth, while 

 under my observation, to some half-dozen or more embryos, 

 of oblong or ovate form, which appeared like little Peachias, 

 but I could not see any trace of disk or tentacles in any. 

 They were discharged one by one through the gonidial 

 tube, as the animal lay on its side. 



This one was ruptured in two places; and as it lay in a 

 small tank, the craspedal mesenteries were protruded, and 

 spread in large irregular areas on the glass bottom, per- 

 fectly flat and adherent, the membrane being pellucid and 

 very delicate, and the craspedum bounding the outline like 

 a white thread. 



The conchula is generally protruded, even when the 

 tentacles and disk are wholly retracted. Perhaps it is the 

 seat of some sensation. 



I. Mitchellii. 

 Halcampa. hastata. Cerianthus. 



triphylla. 

 undata. 



and it was only after an hour's labour, when the cavity had become large 

 enough to allow the polype to work in an upright position, and with the 

 assistance of its whole weight, that rapid progress was made." (Annals 

 N. H. for Jan. 1859, p. 78.) 



