Generation of the Lobuluria digitata. > 107 



folds of the canals. Their appearance closely resembled the 

 figures of Mr Ellis ; they were quite visible to the naked eye, 

 and when a section of the animal was placed in water the 

 red ova fell out separately, and sunk slowly to the bottom. 

 -The red colour of these ova is mentioned by Dr Spix, the ova 

 of the Gorgonia and Madrepore have a red colour, and the ova 

 of the Medusa aurita, Lin. are described by Dr Rosenthal 

 (Zeitsck. fur Phys. i. B. s. 328.) as round bodies of a red co- 

 lour, and somewhat lengthened form, which " in their mature 

 state move backwards and forwards in a lively manner without 

 altering their form." The ova of the Lobularia exhibited va- 

 rious shades of colour, from white to deep red, according to 

 their size and maturity. By pressing the red ova between the 

 forceps they were found to consist of a distinct transparent 

 membranous capsule, filled with a gelatinous matter, which ap- 

 peared under the microscope to be composed of the same small 

 globules or monade-like bodies which compose the ova of other 

 zoophytes, and almost all the soft parts of animals. They 

 did not produce the slightest effervescence in nitric acid, al- 

 though every part of the fleshy substance of the adult Lo- 

 bularia contains calcareous matter. By remaining a few days 

 in spirits, or in fresh water, the ova entirely lost their red co- 

 lour, and assumed a yellowish- white appearance even in the 

 centre of entire lobes. 



After a specimen of the animal had remained for some hours 

 suspended in its natural vertical postion in a crystal jar filled 

 with pure sea-water, and its polypi, had fully extended them- 

 selves, I was delighted to find the large red ova beginning to 

 descend from the interior of the canals into the transparent bo- 

 dies of the polypi, where I could easily observe their progress 

 with the aid of a lens, through the sides of the glass vessel. 

 They advanced slowly and only when the polypi were distend- 

 ed. In the space of twenty-four hours ova were seen in the 

 bodies of most of the polypi ; some polypi had only one, several 

 had two or three, and in others groups of four or five ova were 

 observed together placed without any regular order. Many of 

 the polypi had no ova, in others the mouth was seen distended 

 with a single ovum in the act of being discharged, and a few 

 ova were found lying separate at the bottom of the jar. All 



