390 Mr Galloway on Shooting-Stars and Meteors. 



the Meteors called Fire-balls, by Nevil Maskelyne, D.D., F.R.S. 

 and Astronomer Royal," and is dated Greenwich, November 

 6. 1783. After recounting some observations, from which 

 he infers that such meteors appear more frequently than is 

 commonly imagined, and stating the particulars to be attend- 

 ed to in observing them, he adds : — " It would be well if those 

 persons who happen to see a meteor would put down the time 

 by their watch when it first appeared, or was at its greatest 

 altitude, or burst, or disappeared, and again when they heard 

 the sound : and as common watches are liable to vary much in 

 a few hours, that they would, as soon after as may be, find the 

 error of their watch, by a good regulator ; for, if the exact time 

 could be had at different places, the absolute velocity of the me- 

 teor, the velocity of the sound propagated to us from the higher 

 regions of the atmosphere, and the longitudes of places, might 

 be determined^ 



On the Living Iiepresentatives of the Microscopic Animals of 

 the Chalk-Formation. By M. Ehrenberg. 



1. Infusoria of Mexico and Peru. 



M. Ehrenberg communicated to the Royal Academy of 

 Sciences of Berlin, at its sitting on 2d July 1840, a note on the 

 remarkable infusoria living in the seas of Mexico and Peru, 

 which may aid the problematical explanation of the fossil forms 

 of the chalk-formation. 



Notwithstanding the rich materials which the author has 

 already collected from different quarters of the globe of mi- 

 croscopic forms now alive, yet such of those out of Europe as 

 constitute, properly speaking, genera, are still extremely rare. 

 The proper generic forms he Las had an opportunity of ob- 

 serving, whether in Africa or in Asia, have for the most part 

 been since found by him in Europe in the identical species ; 

 and it is very possible that those whose type has not been 

 again met with may have continued in their present rank only in 

 consequence of the series of observations being incomplete, 

 and because they have not been sought after with sufficient 

 care. The forms recently sent from Mexico by M. Carl 

 Ehrenberg, hitherto exhibit only European genera and even 

 European species. The forms of Peru were unknown when 

 the great work of the author on the Infusoria was printed. 



