THE society's NOTE-BOOKS. 207 



of a higher grade than the simpler Polypes, and form a numerous 

 class of their own. Ehrenberg and D'Orbigny have detected 

 hundreds of microscopic fossil species, and it appears that their 

 shells, or outer tissues, enter largely into the composition of chalk- 

 beds, compact mountain limestone (as in Clifton), the flints of the 

 Jara limestone, the Sea-sand of Europe, the Mauritius, the Sand- 

 wich, and other islands, and even the sand of the Libyan Desert ! 

 Some idea of their extreme minuteness may be formed when some 

 levigated whiting is spread out mixed with water and placed under 

 the microscope, when a Mosaic work of these animalcules of varied 

 and beautiful forms may be seen by its means. A power of j^-in. 

 shows the cells in the transverse sections in the slide before us 

 splendidly. E. E. Jarrett. 



The Bryozoa or Polyzoa are, or ought to be at least, familiar to 

 most of our members, the Flustra, or Sea-Mats, being an example 

 of the marine, and Fiumafella, etc., of the fresh water. I have 

 tried, but without success, to see a mosaic of beautiful forms of 

 Bryozoa, or indeed anything else in whiting. Are the Bryozoa 

 animalcules ? Perhaps this depends on what an animalcule is. 



A. Hammond. 



Batrachospermum, To Mount.— I have found no difficulty in 

 preserving Batrachospermum in glycerine by Hautzsch's method. 

 Hautzsch's fluid consists of a mixture of Alcohol, 3 parts ; Dis- 

 tilled water, 2 parts ; and Glycerine, i part. This is nearly of the 

 same specific gravity as water. The specimen is floated in a cell 

 filled with this fluid, and set by, lightly covered to keep out dust. 

 The spirit and water gradually evaporate and leave the glycerine 

 behind. In this way the water in the texture of the plant is gra- 

 dually replaced by glycerine, and we avoid that shrinking from 

 exosmosis which takes place when the specimen is suddenly 

 transferred from water to a dense fluid like glycerine. 



H. F. Parsons. 



Blood, Circulation of, To see.— Dr. C. Hiiter, a German savant, 

 has devised a simple arrangement which makes visible the circula- 

 tion of the blood in the human body. His method is as follows : 



The patient's head, being fixed in a frame, on which is a con- 

 trivance for supporting the microscope and a lamp, his lower lip is 



