392 ANNUAL OF SCIENTIFIC DISCOVERY. 



found also to be an accumulation of pigment and a peculiar form of crystals 

 (not having the chemical reactions of hsematoidine), in the blood. 



In ansAvcr to an inquiry, if the real use of these capsules was known, M. 

 Sequard replied that his hypothesis was that the function of the supra-renal 

 capsules icas to prevent the formation of 'pigment in the blood, and he thinks he 

 has isolated a substance from the blood, which would be changed into pig- 

 ment without the agency of these organs. This substance, perhaps, may be 

 introduced in such a quantity that the capsules cannot destroy it, even when 

 thev arc in a healthy state. In the disease described, a short time since, by 



* * */ 



Dr. Addison of London, and known as bronzed-skin disease, the coloring 

 matter of the skin, examined under the microscope, proved to be the same as 

 that of the negro's skin. And, as in the blood of the same disease, pigment- 

 cells, pigment-granules contained in a transparent substance different from 

 fibrine, and peculiar crystals of an unknown substance, just referred to, are 

 found, he thought there was some ground for the hypothesis that these organs 

 are pigment-destroying agents. He had seen the crystalline plates suffi- 

 ciently large to become impacted in the capillaries and prevent circulation 

 of the blood, and consequently he believed if they were not the prime cause 

 of many disturbances of the nervous influence, they should at least be con- 

 sidered a partial cause. He had likewise observed an absence of blood-discs 

 in the vena cava, which would imply a great alteration of the blood. 



ON THE EXISTENCE OF AIR IN THE BONES OF BIRDS. 



At a recent meeting of the Zoological Society, London, Dr. Crisp read a 

 paper " On the Presence or Absence of Air in the Bones of Birds/' for the 

 purpose of showing the prevailing error upon the subject namely, " that 

 the bones of a bird arc filled with air." Of fifty-two British birds recently 

 dissected by him, only one, the sparrow-hawk (F. nesus), had the bones 

 generally perforated for the admission of air. In thirteen others, the humeri 

 only were hollow, and among these were several birds of short flight. In the 

 remaining thirty-eight neither humeri nor femora contained air, although in 

 this list were several birds of passage and of rapid flight. 



RESPIRATION THE CAUSE OF CIRCULATION. 



The above is the title of a theory recently proposed by Mrs. Emma TVil- 

 lard, the well known authoress, of Troy, N. Y., to account for the circula- 

 tion of the blood, in opposition to the theory of Harvey, which maintains 

 that the impulsive stroke of the heart's beat is the sole motive power. Ac- 

 cording to the views of Mrs. W. the cause of the circulation is to be found 

 in respiration, that function bringing into the lungs, on the one hand, carbon 

 mingled in the venous blood, as the fuel of the animal fire, and on the 

 other, oxygen, derived from the atmosphere, to consume it ; these being in 

 the lungs separated by a membrane, permeable by gases, though not by un- 

 decomposed fluid or air. Thus the carbon and the oxygen intermingling in 

 the lungs, animal combustion ensues, ajjd heat evolved ; this passes into the 



