8 INCIDENTS OF THE VOYAGE. 



projecting from the mouth of the little Spirula, and 

 throwing out their cirri with all the regularity and 

 energy of the larger species. But the most curious 

 thing was a small Porpita, a flat, circular Medusa of 

 about one-sixth of an inch in diameter. It consisted 

 of an annular disk, perfectly pellucid, inclosing an 

 opaque central portion, occupying about two-thirds 

 of the breadth, which seemed to be composed of 

 fibres radiating from the centre. On the under sur- 

 face this central part was flesh-coloured with a blue 

 margin ; and while alive, as it floated, I perceived 

 on it several teat-like projections, which had a slug- 

 gish motion. On the upper side the pellucid mem- 

 brane was continuous, and had a glistening appear- 

 ance ; the opaque part was here light brown. On 

 being handled, the little animal gave out a milky 

 fluid, which clouded the water. 



I afterwards obtained several more of this minute 

 Porpita, some of which were very beautiful; the 

 margin being fringed with numerous oviducts (?) of 

 varying length, which were transparent, but studded 

 and terminated with knobs (germs ?) of a deep blue 

 colour. In the centre of the under surface was a 

 fleshy sucker, and around it many teat-like projec- 

 tions, like the tentacles of an Actinia; these I saw 

 thrown out and suddenly retracted irregularly, and 

 independently of each other.* All these surface- 



* As this seems hitherto undescrlbeil, I propose for it the name of 

 Porpita (polyhrachionea) minuta. It differs greatly in size from those 

 hitherto described, being only one-sixth of an inch in diameter, while 

 I3osc compares P. yic/antea to a 24 sous piece, and P. f/la?t(lifera 

 (figured, of the natural size, in the Phil, Trans, vol. xxiv. p. 2053) 



