226 PROCEEDINGS OF THE SOCIETY. 



Mr. Heath said that shellac was soluble in hot dilute ammonia, and 

 would probably hold Entomostraca with sufficient tenacity. 



In reply to Mr. E. J. Sheppard, Mr. Seoul-field said the cement used 

 need not be transparent. 



Mr. E. J. Sheppard then stated that the dental cement known as 

 " Calxine " set very rapidly under water in considerably less than a 

 minute. It was supplied by Messrs. C. de Trey and Co., 13-14 Denman 

 Street, VV. 



Mr. Maurice Blood remarked that he understood the cement was 

 essentially composed of zinc oxide and phosphoric acid, which be- 

 haved in the same way, and formed a very hard quick -setting cement 

 (i.e. as the preparation mentioned by Mr. Sheppard). He questioned, 

 however, how the phosphoric acid would affect the organisms, and sug- 

 gested zinc oxide and zinc chloride solution, which acted in a similar 

 manner but would not be so poisonous. He also thought that the 

 ammonia in the cement mentioned by Mr. Heath would probably be 

 even more deleterious to these organisms. He asked if the difficulty of 

 retaining Cyclops might not be due to some difference in the surface 

 causing less adhesion of the cement. He further suggested that rubber 

 solution might be tried, but agreed that the petrol used as solvent would 

 almost certainly be too poisonous, and carbon bisulphide worse still. 



Mr. Heath further remarked that a gelatin solution to which a little 

 sugar had been added and into which the wire could be dipped, would 

 set on the wire yet remain insoluble in the water, although it would be 

 tacky and adhesive in the presence of water. 



In reply to a query by Mr. Coon, Mr. Spitta pointed out that gelatin 

 was soluble in hot water but not cold. 



Mr. Coon asked whether Mr. Scourfield had used any special staining 

 methods after preservation, and suggested that Heidenhain's iron-alum 

 followed by Congo-red (^ minute) was useful. 



Mr. Scourfield replied that stains generally penetrated all the tissues 

 without differentiation. Certain results could be obtained by intra- 

 vitam staining with methylen-blue ; certain other stains gave some 

 results in connexion with the nerves, but by the time the stain acted, 

 the normal structure seemed to have broken down. 



Mr. Rogers asked if bird-lime had been tried for fixing purposes ? 

 He had used it with good effect for flies, but for nothing smaller ; it 

 was not soluble in water. Old bird-lime was used. See the Extra 

 Pharmcopceia (Martindale), 14th ed., 730. 



The President remarked that the discussion, ranging from old bird- 

 lime to the modern kinematograph, had been of a most interesting 

 nature. One reagent had not been mentioned in connexion with stain- 

 ing, especially with intra-vitam staining : Ehrlich's neutral red. In leuco- 

 cytes, this stain brought out the changes resulting fiom phagocytic 

 action with great distinctness, and marked the active cells as compared 

 with the cell in which there was no functional activity. He thought 

 they would agree that they owed their very hearty thanks to Mr. Scourfield 

 for bringing forward his communication in such an interesting fashion. 



The vote of thanks was cordially acknowledged by all present, and 

 passed unanimously. 



