Zoological Society. 341 



granular, and in about the same degree as the colourless corpuscles 

 of blood, and the ordinary exudation corpuscles, to which they pre- 

 sent a strong resemblance. 



ilany of these bodies preserve their figure for a considerable time, 

 while others become collected into clusters and form irregular broken 

 masses. 



The coloured corpuscles are irregular in size and shape, and are 

 composed of an aggregation of minute elongated and sometimes 

 triradiate bodies, many of which appear, from their irregular and 

 obscure outline, as though partially dissolved. In the immediate 

 neighbourhood of these, the fluid has a much deeper colour than 

 elsewhere. From these circumstances I have been led to conclude 

 that the general pink colour of the fluid is due to the solution of the 

 coloured particles, and not simply to their presence. In this parti- 

 cular the fluid under consideration is strikingly difi'erent from blood, 

 which owes its colour to the presence of coloured globules and not to 

 their solution. 



Whether the red colour of the exudation is a condition of youth, 

 and of an imperfect condition of the skin, and has ceased in con- 

 sequence of the increased age of the animal and the consequent more 

 perfect development of the integument, or has ceased in consequence 

 of the change of climate to which the animal has been lately subjected, 

 is a question which, with the facts at present a* our disposal, can- 

 not be satisfactorily determined. 



We have however sufiicient evidence to warrant the conclusion, that 

 the thick tenacious exudation, whether coloured or otherwise, is 

 poured out only during the time the skin is immersed in water, and 

 that it has an especial reference to the aquatic habits of the animal, 

 it appears for the time to convert the surface of the body into a mu- 

 cous membrane, and then, on the animal lea^'big the water, to furnish 

 by its inspissation an epidermis. 



Should further inquiry show that the thickness of the exudation 

 arises from a solution of the colourless globules, its relation to mucus 

 will be still further established, and a microscopic examination into 

 the structure of the skin will become a subject of great physiological 

 interest. 



3. On six new species of Humming Birds. 

 By John Gould, F.R.S. etc. 



Although the Trochilidae have lately received much attention both 

 from our own and the continental naturalists, the subject is far from 

 exhausted, as is shown by the circumstance of my being able to bring 

 before the notice of the Society this evening no less than six species 

 hitherto uncharacterized and unknown. These great accessions to the 

 family are all from a state with which we have as yet had but little in- 

 tercourse — that of Yeragua in Central America ; and we are indebted 

 for a knowledge of them to the researches of an enterprising traveller 

 and botanist, M. Warzewicz, who has just returned from that coun- 

 try, where he successfully explored many forests and other districts 

 not previously trodden by the foot of civilized man. Unfortunately, 

 both for myself and for science, he was not able, in consequence of the 



