154? Sir John Graham Daly ell on a Singular Mode of 



I kept the animals carefully, and obtained correct drawings 

 of several specimens. They disappeared again ; but now va- 

 rious minute spots, such as indicate originating zoophytes, re- 

 mained. 



Meantime, having been replaced by a new colony, the spi- 

 nulae after exhibiting equal activity remained in a vertical po- 

 sition ; the head in contact with the bottom of the vessel, and 

 nearly in a state of repose. Next the front of the head en- 

 larges, angular projections issue from it, and incipient adhesion 

 by one or more of them ensues. As if unwillingly arrested, 

 the animal then exhausts itself in convulsive struggles to be free. 

 The vibrations of the tail are so quick that the eye can scarcely 

 distinguish its figure. At length motion ceases ; and it becomes 

 irreversibly rooted. 



In a few days, a manifest change is discovered. A dark so- 

 lid nucleus occupies the place of the head or body of the spi- 

 nula, and its tail has disappeared. A transparent matter has 

 diffused around the front, towards the circumference of which 

 twenty-six or twenty-eight flattened radicles are diverging from 

 the nucleus as a centre, and distributed among it. (Fig. 2.) 

 Meantime, the nucleus is consolidating, two nipples with qua- 

 drangular orifices rise from the upper side. The radicles be- 

 come inconspicuous below ; the transparent matter forms a 

 skinny environing basis, and the spinula proves to have been 

 metamorphosed to a nascent ascidia. 



This animal may be now recognised as one the most com- 

 mon in our seas. Few marine collections are made without its 

 presence on one or other part of them, which accounts for its 

 being almost a constant concomicant on the Flustra carbasea. 

 When mature, it is of various shades from peach-blossom red 

 to, carmine; and then it might be inscribed in three-fourths of 

 a sphere, six or eight lines in diameter. (Fig. 3.) 



The young ascidiae bred from the spinulae, began to colour 

 in three months. 



This species which is here denominated Ascidia papilla pro- 

 visionally, belongs to a genus approximating the Cynthia of the 

 learned naturalist Savigiiy. The orifices of the papillae, or 

 nipples, are quadrangular, but these parts themselves are not 

 furrowed or fluted, as those described by that author. 



