114 transactions. — Miscellaneous, 



matter, and subsequently of vaccine lymph. These experiments were only 

 partially successful for reasons which are now obvious ; but they led on to 

 other experiments. 



Mainly these were on the growth and development of the red corpuscles 

 in birds. The results of these experiments were published in the Trans- 

 actions of the New Zealand Institute for 1874. It was shown that by the 

 use of a suitable nutrient fluid — egg-albumen mixed with water — the nucle- 

 ated red corpuscles could be made to grow and throw off their nuclei, which 

 became developed into round coloured non-nucleated corpuscles, exactly 

 resembling those of mammalia. The same experiments, with a like result, 

 were made with the blood of fishes, particularly with sharks and rays, and 

 subsequently with the blood of reptilia. 



During the investigations upon the blood of reptilia, (frogs being selected 

 for convenience), I naturally took the opportunity of observing the pheno- 

 mena of inflammation, as seen in the web of the frog's foot and the tail of 

 tadpoles. Having for some time entertained grave doubts, on a priori 

 grounds, as to tbe possibility of Cohnheim's so-called wandering corpuscles 

 really passing through the walls of the capillaries, I was induced to make 

 some experiments with a view of testing the matter. 



For this purpose I took advantage of a few months' residence in New 

 South Wales, not only carefully and repeatedly to examine with the micro- 

 scope, the phenomena of inflammation in the tails of tadpoles, but also to 

 show, beyond the possibility of doubt, that leucocytes do not, in these 

 animals, wander fi-om the blood vessels, but are formed from pre-existing 

 germs in the solid tissues, either from connective tissue corpuscles or from 

 some other source. A very simple experiment showed this. A small 

 portion of the transparent extremity of a tadpole's tail was cut off, and im- 

 mersed in a nutrient fluid, (half egg-albumen and half water was found 

 the most useful), and kept at the ordinary temperature of the air, which at 

 that place and season varied fi-om 70° to 90° F., in the house. Control 

 experiments were made by immersing other portions of tails in water, in 

 water impregnated with carbolic acid, and in various other media. The tails 

 immersed in pure water were in a few hours in a state of decomposi- 

 tion, sulphuretted hydrogen was evolved, bacteria and multitudes of animal- 

 cules (monads) were formed in the water, the portion of tail was shrivelled, 

 and dead to all intents and purposes. With carbolic acid the tails under- 

 went no change. 



The following description, taken from the notes of one experiment, will 

 show the changes that ensue in a few hours : 



" March 13th, 1878, 2.80 p.m. — Snipped off four tadpoles' tails, placed 

 them in a mixture of egg-albumen and water. Tails sank in mixture. 



