= 
ON INFECTIVITY, ETC., OF THE OYSTER. 669 
oyster are still under investigation, and we hope to give a fuller account of 
it in our next report. We do not doubt that these oysters are in a 
thoroughly healthy condition, and their colour is not due to copper or iron. 
There is, however, a pale greenness (quite different in appearance from 
the blue-green of the ‘ huitres de Marennes’) which we have met with in 
some American oysters laid down in this country, and which we regard 
as a disease. It is characterised by a leucocytosis in which enormous 
numbers of leucocytes come out on the surface of the body, and especially 
on the mantle. The green patches visible to the eye correspond to 
accumulations of the leucocytes, which in mass have a green tint. These 
cells are granular and ameboid. The granules do not give any definite 
reaction with the aniline stains, and so far we have not made out their 
precise nature. Associated with the green disease we have found numerous 
exceedingly small flagellate organisms both in the blood and in the green 
patches, and observations so far lead us to believe that there is some 
relationship between the two. We have tried growing oysters under 
various unusual conditions, including the addition to the sea-water of 
fluids from alkali works, such as may enter our estuaries, in the hope of 
getting some clue to the cause of this green disease, but have so far failed 
to reproduce exactly in the laboratory the changes which apparently take 
place in nature. Our present opinion, however, is that oysters exhibiting 
this pale-green leucocytosis are in an unhealthy state, and we may add 
that we find the liver in these specimens is histologically in an abnormal, 
shrunken, and degenerate condition. Whether actually ‘unfit for food’ 
or not, they are at any rate in very ‘poor’ condition, and have lost the 
aroma and flavour of the normal healthy oyster. 
For much assistance in connection with this research the authors 
acknowledge their indebtedness to Mr. Andrew Scott, Drs. Abram, Evans, 
and Balfour Stewart. 
Physiological Applications of the Phonograph.—Report by the Com- 
mittee, consisting of Professor JoHN G. McKEnpRICK (Chairman), 
Professor G. G. Murray, Mr. Davin 8S. WINGATE, and Mr. 
Joun S. McKenprick, on the Physiological Applications of the 
Phonograph, and on the Form of the Voice-curves made by the 
Instrument." 
1. THE work of the Committee has, during the past year, been directed 
to improving the method by which the curves of the phonograph may be 
transcribed. The arrangement described in the ‘Journal of Anatomy 
and Physiology ’ for July 1895 has been much improved in two respects : 
(1) by driving the phonograph at a slow rate by a small electric motor ; 
and (2) by adapting the recording lever, now made of aluminium, to a 
new form of siphon recorder.? In this way beautiful curves may be 
obtained, amplified from 500 to 800 times, and on strips of telegraph 
1 See Brit, Assoc. Report for 1895, p. 454. 
2 The Committee are much indebted to Lord Kelvin for encouragement during 
the research. They also desire to express their obligations to Mr. Reid and to Mr. 
Keen, of James White and Co., for executing the mechanical devices employed. 
