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spheroidal tubercles, which were more or less thickly disposed on 
all diatom valves. 
Dr. Eulenstein took the opportunity of mentioning that he had 
purchased the late Dr. Arnott’s tubes of diatom material, and 
was prepared to issue series of the species in this collection (the 
most complete British collection) on application. 
Mr. Beck called attention to the fact that his brother, the late 
Eichard Beck, had urged the probability of the spherical character 
of the diatom markings, and had shown by photographs of a 
piece of glass marked with hemispherical protuberances how an 
hexagonal or dotted appearance could be obtained by varying 
the illumination. 
Mr. Jabez Hogg read a paper entitled “ Eesults of Spectrum 
Analysis,” in which he gave some of Mr. Sorby’s observations, 
published more than a year since in the Eoyal Society’s pro- 
ceedings, and also exhibited a drawing of chlorophyll spectra, by 
the late Dr. Herapath. 
Mr. Eay Lankester expressed his disappointment at the incom- 
pleteness and inaccuracy of Mr. Hogg’s paper. He pointed out 
several fallacies and mistakes in Mr. Hogg’s statements, such as 
the asserted presence of haemoglobin in the blood of the house-fly, 
in which animal its presence is really due to its having been 
taken in as food, and is met with only in the alimentary tract ; 
the asserted discovery of copper in turacin by the spectroscope, 
which was a complete misrepresentation, since Professor Church 
had discovered the copper before the absorption bands ; and the 
supposed connection of thallium and chlorophyll, which Mr. Hogg 
had ventured to suggest. Mr. Lankester pointed out that Mr. 
Hogg had omitted all reference to the really valuable physiolo- 
gical results obtained by examining the action of gases on the 
blood with the spectroscope, and had also not mentioned its use 
in detecting haemoglobin and chlorophyll in the lower animals, 
which he (Mr. Lankester) had written upon. Mr. Hogg bad 
pretended that sodium could be recognised in increased quantity 
in a cataract-lens by means of the spectroscope. This Mr. 
Lankester entirely denied. 
