352 Messrs. Podc and Lankester on the Development [June 19, 



Tube 8. Quantity aud character of the infusion as in 4 and 5, but the 

 tube sealed without previous ebullition. 



Tubes 9, 10, 11. Quantity and character of the infusion as in 1, 2, 3, 

 but rendered slightly alkaline with KHO. Sealed approximately during 

 ebullition. 



All these tubes (1 to 11) were after closure completely submerged in 

 boiling water for fifteen minutes, and were then preserved in a hot-air 

 bath, varying in temperature from 30° G. to 35° C. 



Microscopic and naked-eye appearances of the hay-infusion at the time of 

 sealing the tubes. — The infusion in tubes 1, 2, 3, 6, 7 was clear and 

 pellucid, that in tubes 4, 5, 8, 9, 10, 11 was hazy. 



Microscopic examination gave the result indicated above, as to the 

 appearances of freshly prepared hay and hay-and-cheese infusion. 



Subsequent appearances of the infusion in Tubes 1—11. — The tubes 

 with infusion which was pellucid at the first were found to retain this 

 character for several weeks, being preserved in the air-bath and 

 examined from day to day. The hazy infusions were opened after four 

 days, and their contents found to be unchanged. 



A portion of the same hay-and-cheese infusion, boiled and purposely 

 contaminated by preservation in an uncleaned beaker, was found after 

 four days to be teeming with Bacterium termo exhibiting vital movements. 

 The pellucid infusions were subsequently examined with the microscope 

 at different times and found to be unchanged. 



Seeies B. Nov. 25th. Experiments ivith turnip-and-cheese infusion. — 

 An infusion was made with 700 grms. sliced white turnip and 1000 grms. 

 water, to which about 1 grm. finely minced new cheese was added, the jug 

 containing the mixture being maintaiued for four hours on a sand-bath at 

 a temperature of 45°-55° C. 



The infusion was now filtered ; sp. gr. of the infusion 1011*1. Eeac- 

 tion slightly acid. 



Tubes 12, 13, 14. Sealed cold. Submerged in boning water for thirty 

 minutes. 



Tubes 15, 16, 17, 18, 19. Sealed approximately during ebullition. 

 Submerged in boiling water for thirty minutes. 



The tubes were preserved in the air-bath as in Series A. 



Microscopic and naked-eye appearances of the infusion at the time of 

 sealing the tubes. — The liquid in all the tubes was perfectly clear and 

 limpid. A few shreds and flakes were obvious, which appeared to be 

 derived from the filter-paper and from the slight precipitation of albu- 

 minous matter. The microscopic appearances were those above described 

 as characterizing such infusions. 



Subsequent appearances of the infusion.— -The infusion in all the tubes 

 was found on examination from day to day to retain its limpidity. Sub- 

 sequent microscopic examination of all the tubes at various periods sub- 

 sequent to the closure of the tubes (from four days to three weeks) 



