Physics and Chemistry. | 121 
podia as has been done by Stimpson. The gastric region is 
narrow and projects far forward as in the Maioids, The ex- 
pansions on the sides of the carapax, which give it a Cancroid 
form, are thin, and contain none of the internal organs, and 
their removal would give the carapax very much the form of 
Cryptopodia. 
SCIENTIFIC INTELLIGENCE. 
I, PHYSICS AND CHEMISTRY, 
1. Spectroscopic observations of the Sun.—LockyER has com- 
municated a number of interesting facts resulting from his further 
observations on the spectroscopic phenomena of the sun. Of: 
these the following are especially worthy of notice. 
(1.) The lines of magnesium, sodium and barium when observed 
in a spot, are thicker than their usual Fraunhofer lines. 
2. e same lines when observed in the chromosphere are 
thinner than their usual Fraunhofer lines. 
even near a prominence. € prominences sometimes un 
very marked changes in a few minutes; in one case, in about 
minutes, a portion of one about 27,000 miles in height entirely 4 
peared, another portion of the same protuberance increasing 2 
the same time. In a former paper Mr, Lockyer pointed out the 
