Astronomy. 163 
5. Arrangement oy the Perissodactyles, with a note on the 
Structure of the foot of Toxodon, by E. D. Corz.—Proceedings 
of the American Philosophical Society, April 15, 1881. 
ITV. ASTRONOMY. 
1. Photographie Spectrum of Comet 1881, 6; by WM. Huearns. 
—On Friday night (June 24th), I obtained with one hour’? 8 exposure 
shows a pair of bright lines a little way aay H in the ite 
violet region, which appear to belong to the spectrum of carbon 
(in some form) which I observed in the visible region of the 
spectra of telescopic comets in Abies and pet here is also in 
hotogra 
was reflected solar li ht. 
This photographic evidence Sapper the results I obtained in 
1868, showing that comets shine partly by reflected solar light, 
and partly by their own light, the spectrum of which indicates 
the presence in the comet of carbon, possibly in combination 
win be hydrogen,— Communication from the Author; also Nature, 
2. Notice of the Comet; by Cuartes E, Burron.—At about 
11h. Om. G.M.T. on June 29, a transit of the “following” nuclear 
jet of the great comet over a star of 8m. was observed ‘by a N. 
E, Green, of 39 Circus Road, St. John’s Wood, and by me, with 
a 124-inch reflector belonging t o Mr. Green. Definition was very 
good and tranquil. eth he star ents involved in the jet it 
gradually increased in size, and, when seen through the brightest 
part of the jet cayEned ‘resembled an ill-defined planetary disk 
about 3” in diameter. t this moment the comet seemed to have 
two nuclei similar in “aspect and brightness. 
The effect of the cometary matter on the star’s image resembled 
that of. fickle glass, not that of fog; the image of the star, being 
dilated into a patch of nearly uniform brightness, instead of pre- 
senting a sharp central point with a sures halo. Cirro- 
Stratus, passing into rain-cloud, produces on i apaypre of 
the sun an effect the counterpart of that Kaas by the come- 
tary emitted matter on the star. There was not sufficient i ht 
for the use of the spectroscope, sca niet afterwards identified as 
- +65°, 519, being fainter tha 
‘The transit of the jet sesuiind! sous 3m. and the star slowly 
resumed its ordinary appearance and dimensions, the image con- 
tracting as the center of the jet left the star behind. A transit 
of this kind has oh sajieisr ntly been observed, at least under such 
favorable conditions as to brightness and definition of the objects, 
and it is to be ho poll that others may have been as fortunate as 
Mr. Green and the undersigned. 
If the point, which obeys the Newtonian law, be a solid body, 
the observation just recorded seems to show that its true outline 
