162 THE AMEBIC AK MONTHLY [June, 



Crenation of Red Blood-Corpuscles. 



By M. L. HOLBROOK, M. D., 



NEW YORK. 



The ci'enation, or formation of notches along the borders of the 

 red blood-corpuscles soon after they have been put on the slide for 

 the microscope has been observed by all who have studied the 

 blood even cursorily. I have made observations of this feature of 

 the corpuscles in a large number of cases and have observed the 

 following facts : 



The crenations are most numerous and form the most quickly in 

 persons in good health and with a vigorous constitution and when 

 the color is of a pronounced red. 



In a chlorotic girl, with a rather poor constitution, it was sev- 

 eral hours before any crenated, and then only a few. In her case 

 the blood was very pale. When she had improved in health the 

 crenations were more numerous and appeared quickly after the 

 specimen was placed under the microscope. In a very delicate 

 child scarcely any crenated, even after a long time. It has been 

 claimed by some microscopists that alcoholic drinks are a cause of 

 it. I made special note on this point and found just the reverse ; 

 that in abstainers from alcohol, if the constitution is good, crena- 

 tion takes place soon. In one case, nearly all were crenated 

 within a few moments, except in that part of the field where they 

 were crowded together so as to press on each other very closely. 

 If the droplet of blood is put upon a slide with an oil frame around 

 t to prevent evaporation, in most cases the crenations disappear 

 after 73 hours. 



The late Dr. Elsberg, who studied the corpuscles treated with 

 bichromate of potash and made the discovery that each one has a 

 reticular structure, claimed that the crenation was due to a con- 

 traction of this reticulum. I have no doubt of the correctness of 

 his conclusion, and this will, I think, explain the reason for more 

 vigorous and general crenation in cases of a good constitution than 

 where it is ver}' poor. There is more living matter in such cases 

 and more power to contract. It would also explain why the cre- 

 nations generally disappear after a few da\s. The living mat- 

 ter dies and loses its contractile power when the corpuscles swell 

 out by taking in the fluid in which they are immersed. 



The haematoblasts in the blood never become crenated, but I 

 have in one specimen of blood seen a few with delicate thorn-like 

 projections from their margins. This was in the case of a man 

 about 60 years old and somewhat broken down in health. In his 

 case the haematoblasts were abnormally numerous, amounting, on 

 a rough estimate, to about one-fourth as many as of red blood-cor- 

 puscles. 



