210 JOURNAL OF THE [November, 



Chalcedony Park, the name given to the area of one thous- 

 and or more acres in which occur the jasperized or agatized 

 trees of which mention was made in the meeting of October 2d, 

 is situated a few miles from Corriza, a station on the Atlantic 

 and Pacific Railroad. The trunks are partly buried in beds of 

 lava and sandstone, and large wheel-like fragments lie scattered 

 about. The substitution of silex for woody fibre must have 

 been effected through the agency of siliceous waters. 



Under a good microscope — a binocular is best — a piece of 

 coniferous wood, illumined from above, will often be semitrans- 

 parent to a depth of the aggregate thickness of three or four 

 plates of cells. It thus, with its several ranks of lenticular mark- 

 ings, becomes a more beautiful object than when, in thin 

 section, it is viewed by transmitted light. We have had oppor- 

 tunity to examine the silicified wood from Chalcedony Park only 

 as an opaque object. Some of the specimens exhibited with 

 gteat distinctness the structure just described, but of a beauty 

 far more striking, owing to the crystalline character of the 

 material and the exceeding richness of the coloring. 



Cocaine Hydrochlorate for Mounting Animalcula. — 

 The action of the reagents in general use for killing animalcula 

 for mounting disturbs the natural appearance and position of 

 such delicate structures as the tentacles of Hydroids and 

 Bryozoa. Prof. J. Richard has successfully employed in these 

 cases the anaesthetic power of cocaine hydrochlorate. Several 

 o( the animalcules are placed in a watch-glass with five cubic 

 centimetres of water. When they are fully expanded a ^ per 

 cent, solution of cocaine hydrochlorate is added drop by drop 

 until it forms a fifth part of the entire fluid. Half a cubic cen- 

 timetre of the anesthetic is then added, and the animals become 

 completely fixed. Ten minutes afterward they are quite dead, 

 and can be mounted in the ordinary way. — See Jour. Roy. Mic. 

 Soc, 1885, p. 893. 



Professional Microscopy. — So long as mind is associated 

 with matter, uses its energies, or is obstructed by its limitations, 

 will the knowledge of the laws of physical life interest man 

 nearly, and aid him to his goal. Indeed, biological investigation 

 is, if we mistake not, the most absorbing of present jiurely sci- 

 entific pursuits. The nature of the force called life may con- 



