366 JOHN F. FULTON, JR 



regards the olomonts, but as regards the formation of highly 

 complicated compounds.' Though the earlier writers con- 

 sidered that there were no spectroscopic variations between the 

 haemoglobins of various animals, more recent work has shown 

 that there are minute differences even between the spectral 

 bands of ethiopian haemoglobin and that of the white races. 

 Eecently Vies (1919) made a careful investigation of the haemo- 

 globin of Arenicola piscatorum, Lk. and of Marphysa 

 sanguine a, Quatref., and has found certain pronounced 

 differences between their spectra and that of vertebrates. 



With such facts as these one cannot avoid agreement with 

 Griffith's contention that haemoglobin is the product of a long 

 and complicated phylogenetic development. Sorby (1876), 

 in a paper on the evolution of haemoglobin, held that the 

 substance had its beginning as a bile pigment (non-respiratory) 

 such as exists in Helix aspersa. The next step was found 

 in the haemoglobin-like pigment of Planorbis, which is respira- 

 tory. The final stage is seen in the concentration of haemo- 

 globin into individual cells, a condition such as one finds first 

 in the blood corpuscles of Gephyrea, and later in the vertebrate 

 erythrocytes. 



Eeichert and Brown (1909), in their monumental work on 

 the crystallography of the haemoglobins, have urged, since 

 there is a characteristic crystal form for the haemoglobin of 

 every species, that the haemoglobin of each species is chemically 

 different from that of every other, and that a specific crystal 

 form is an expression of a specific chemical molecule. But, 

 ' it is well known that crystal-habit is modified by the altera- 

 tions of the medium from Mhich the crystals are deposited ', 

 and since it is a matter of common knowledge, particularly 

 in the light of modern bacteriology, that the blood plasma of 

 animals differs profoundly betw^een individuals (even of the 

 same species), and since the haemoglobin crystals of each 

 species studied by Eeichert and Brown were deposited from 

 a different medium, ' it is not improbable that the observed 

 differences in the crj^stals are attributable to these known 

 differences in the media in which they were formed ' (Eobert- 



