92 PREPARATION AND STUDY OF HEMOGLOBIN CRYSTALS. 



Schmidt (Preyer, De hsemoglobino observationes et experimenta, Bonn, 

 1866) gives the following analysis and molecular formula for the hemoglobin 

 of the dog: 



During this same year Moleschott (Pathologic u. Physiologie, 1866, 42) 

 made note of the occurrence of six-sided plates in guinea-pig blood. 



Nawrocki (Centralblatt f. med. Wissensch., 1867, xv, 195) and shortly 

 after Ray Lankester (Jour. Anat. and Phys., 1868, u, 114) established the 

 identity of the coloring matters of the bloods of the worm and vertebrates. 



Hoppe-Seyler (Medicinisch-chemische Untersuchungen, 1867, Heft 2, 1, 

 215, 293; Heft 3, 366, 394) at about that time prepared crystals from a 

 number of bloods of different species, and made elementary analyses and 

 observations in various directions. His elementary analyses of the hemo- 

 globins of the dog, goose, guinea-pig, and squirrel will be found in the 

 table on page 71. Kuhne (Lehrb. d. physiol. Chemie, 1868, 198) recorded, 

 among other kinds of hemoglobin crystals already obtained, that of the 

 polecat. At this time Ray Lankester began the publication of a series of 

 articles on the distribution of hemoglobin in the animal kingdom, which 

 articles have been referred to in Chapter I. 



In a research on the cellular structure of the red blood corpuscles, 

 Richardson (Trans. American Med. Association, 1870, xxi, 261) studied 

 intracorpuscular crystallization in the menobranchus. The corpuscles 

 being very large and the hemoglobin readily crystallizable lend condi- 

 tions extraordinarily favorable to such observations. He deposited a drop 

 of blood upon a slide, allowing it to remain uncovered about 10 minutes, 

 or until a mere line of desiccation appeared at the margin, and then cover- 

 ing it with a thin glass. On examination with a power of 200 diameters, 

 he found that numerous corpuscles along the edge of the drop, where the 

 liquor sanguinis had become concentrated, contained one, two, or more crys- 

 tals; and under favorable conditions this process of crystallization went 

 on until the contents of every corpuscle assumed a crystalline form, either 

 wholly or in part. The crystals were frequently irregular, but their typical 

 form appeared to be that of a quadrangular prism with dihedral summits, 

 the angles being sometimes truncated. 



