2l6 PROCEEDINGS OF THE COTTESWOLD CLUB 



balsam. Foraminifera, Ostiacoda, and Polyzoa are best, 

 I think, when mounted dry as opaque objects ; but 

 if it is desired to mount the Foraminifera in balsam, I 

 consider the best process to be, to put some of the 

 material, which must be perfectly dry, into a small test 

 tube with some spirit of turpentine, and boil it until all the 

 air has been expelled from the interior. \'ery little 

 turpentine suflices. When the air has been expelled, drop 

 in some pure balsam, and keep at a considerable heat for 

 a short time in order to evaporate the turpentine, stirring 

 the material so as to dis.seminate the organisms equally 

 throughout the mass. The balsam with its contained 

 forms may then be taken up with glass rod or a piece 

 of wire, and placed upon covering glasses. The organisms 

 may then be mounted without the slightest difficulty, and 

 without any air bubbles. 



The annexed Plate A illustrates certain of the organisms 

 to which reference has been made in the text, as well as 

 other noticeable forms. It will give some idea of the 

 interesting and varied microzoa, whose remains, as the 

 microscope reveals, make up the substance of what is 

 known as chalk. 



EXPLANATION OF PLATE A. 



Fig. I. Foraminifer, Genus? ■ 95. 



Fig. 2. Gaiidryina sp., x 120. 



Figs. 3-5. Biiluniiia sp. var., x 58. 



Figs. 6, 7. Fyondiciilaria sp. var., x 58. 



Figs. 8, 9. Textiilaria crctacea, x 76. 



Figs. 10, II. Piillciiid sp., X 58. 



Fig. 12. Glaiiduli)ia sp., 38. 



Figs. 13, i.j. Rotalia sp., 40. 



Fig. 15. Textidaria sp., >~ 40. 



Fig. 16. Wheel oi Cliirodota, x 200. 



All the .specimens are from the Upper Chalk, Purle)^, Surrey. 



