TRANSACTIONS OF THE SECTIONS. 81 


Observations and Experiments on the Noctiluca miliaris, the Animalcular 
Source of the Phosphorescence of the British Seas; together with a few ge- 
neral remarks on the phenomena of Vital Phosphorescence. By Dr. J. H. 
Prine. 
The author referred to the various theories which have been advanced on the sub- 
_ ject of the phosphorescence of the seas, and to the instances of phosphorescence occur- 
' ring both amongst land and marine animals. After reciting various observations by 
others on the phenomena of vital phosphorescence, he proceeded to detail his own 
experiments at Weston-super-Mare, upon a small vesicular animal, not exceeding the 
one-thousandth part of an inch in diameter, which possessed. very remarkable lu- 
minous properties, This animal the author believed to be the Noctiluca miliaris, 
and he regarded it as the most common source of the phosphorescence of the British 
seas. It occurred sometimes in such large quantities, and was so luminous, as to give 
the sea the appearance of a sheet of fire. Viewed by aid of the microscope, the 
animalcule is seen to consist of a spherical portion, and a tentaculum, which appears 
to be a motor organ. It does not appear to possess any special luminous apparatus, 
but the phosphorescent power is believed by the author to reside in a flocculent mucus 
secreted by the littleanimal. In giving the results of his experiments on the light 
emitted, the author found that galvanism produced no perceptible effect, but the 
electro-magnetic current sensibly increased the luminosity. Oxygen gas increased 
the light, without exerting any marked influence over the duration of the life of the 
animal, Contrary to what might have been expected, carbonic acid gas was likewise 
found to increase the light to a very remarkable degree, far exceeding in this respect 
the effects of oxygen ; but the animal was killed by it when immersed in it only for 
_ acomparatively short space of time. Sulphuretted hydrogen speedily deprived the 
_ animal of life, and consequently destroyed the light; nitrogen, nitrous oxide, and 
hydrogen produced little or no effect on the luminosity ; strong mineral acids in- 
creased for a moment but speedily afterwards destroyed the light; ether instantly 
destroyed the life of the animal; chloroform increased the light and then destroyed the 
animal. The author then instituted a comparison between his own experiments and 
_ those of Prof. Matteucci on the glowworm; and after examining the various theories 
_ put forward to account for the luminosity of animals, concluded that the phenomena 
could not at present be referred to any more general fact with which we are ac- 
 quainted. 
























Notice of two additional bones of the Long-legged Dodo or Solitaire, brought 
a Srom Mauritius. By H. E. Srricxuanp, M.A., F.G.S. 
These bones have been recently sent to England by the officers of the Royal Society 
_ of Arts and Sciences of Mauritius. They consist of two tarso-metatarsal bones, of 
" which one is incrusted with stalagmite, and seems to belong to the same individual as 
_ those figured in the ‘ Dodo and its Kindred,’ plates xiii. xiv., which are now in the Paris 
Museum. The other specimen is far more perfect than any examples of this bone 
_ before known, but though apparently belonging to an adult individual, it is of small 
dimensions, being only 5 inches 8 lines in length. The only defective portion is the 
" posterior surface of the ecto-calcaneal process, which is slightly abraded. The form 
_ of the bone precisely agrees with that of the Solitaire, and though of small size, it is 
_ doubtless identical in species with that bird. — It exhibits in great perfection all those 
peculiar characters which prove both the Dodo and the Solitaire to have been closely 
allied to the family of Pigeons; especially the position of the caleaneal canal, which 
in those birds passes externally to the posterior ridge, whereas in the gallinaceous 
hirds it passes on the inside of that ridge. 
__ The author took this opportunity to allude to a paper on the Dodo, in the Boston 
Journal of Natural History, in which Dr. Cabot, though wholly unacquainted with 
the researches of Mr. Strickland and Dr. Melville, arrives independently at precisely 
‘the same conclusion, viz. that “ the Dodo was a gigantic pigeon.” 
a On the Growth of Silk in England. By Mrs. Wurtsy. 
_ I had proposed offering to the British Association a short account of my progress 
in the art of cultivating silk in England, but I left Newlands before all the produce 
(1849. ss 6 
i 
