BIOLOGICAL AND MICEOSCOPIOAL DEPAETMENT 



ACADEMY OF NATURAL SCIENCES. 



January 4th. 



Mk. J. D. Sergeant in the Chair. 



Twenty-one members present. 



Dr. McQuillen remarked that, in conjunction with Mr. Walmsley, he had 

 made some attempts to mount blood corpuscles in such way as should main- 

 tain their natural shape. In solutions of glycerine and water, the form of 

 the corpuscle of the frog had rapidly altered, but Mr. Walmsley had mounted 

 some in glycerine jelly which remained unaltered up to date. 



Dr. Tyson stated that to expect success with the aqueous preservative fluids 

 was scarcely reasonable, unless a menstruum were used identical in its 

 specific gravity with the liquor sanguinis of the blood. Such a solution can 

 be obtained with glycerine and distilled water, in the proportion about fzij 

 of Bourn's glycerine to f5iiss of distilled water, and if one part of carbolic 

 acid be added to 100 parts of the mixture, a suitable preservative fluid is ob- 

 tained for many animal tissues. 



January 18th. 

 Director S. W. Mitchell, M. D., in the Chair. 

 Twenty-four members present. 



Dr. Wood exhibited to the department four species of the genus Sirosiphon, 

 all of which he stated to be new to North America, and three entirely unde- 

 Bcribed. One of them had been found growing on the face of a wet rock on 

 the banks of the Wissahicon, by Dr. J. Gibbous Hunt, from whom he had 

 received specimens. These are referable to Sirosiphon pulvinatus of Europe. 



Two of the new species were collected in South Carolina, by Prof. H. W. 

 Ravenel, who sent them to Dr. Billings, U. S. A., to whom Dr. W. stated he 

 was indebted for the specimens. The following are the descriptions : 



S. LiGXicoLA. — S. strato expanso, tomentoso, atro ; trichomatibus ramo- 

 sissimis, arete intertextis : ramulis abbreviatis vel elongatis, subrectis aut 

 varie curvatis, apice obtuso rotundatis vel subacumiuatis ; trichomatura et 

 ramulorum cellulis internis uni-biseriatis, plerumque pachydermaticis, dilute 

 vel saturate ferugineis, enormibus, plerumque homogeneis terminalibus elon^ 



