162 TlIK AMKKICAX MONTHLY [Juiif, 



( it'Tiatioii ol' |{t'<l Hl(»<»(l-('<)i'|)iis('l(>s. 



Mv M. L. IIOLIJROOK. M. 1).. 



NKW VI IKK 



Tlic crcnatiun. ov tonuMtioii of notclicj^ ;iluii<; the liordcis ol the 

 reti Mood-corpuscles soon after they liave 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 larjje niunber of cases and liavc observed the 

 follo\vin;4 facts : 



The crenations are most numerous and form tlie most(|uicl<h in 

 persons in j^ood healtii and with a vigorous constitution and wiien 

 the color is of a pronounced red. 



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

 eral hours before anv crenated. and then onlv a few. In her case 

 the blood was verv pale. When she had improved in healtii the 

 crenations were more numerous and api)eared quickly alter the 

 specimen was placed under the microscope. In a very delicate 

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

 claimed bv 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 soo!i. In one case, nearly all were crenated 

 within a few moments, except in that part of the Held 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 72 hours. 



The late Dr. Elsberg. who studied the coipuscles 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 very poor. There is more living matter in such cases 

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

 nations generallv disappear after a few days. The living mat- 

 ter dies and loses its contractile power when the corpuscles swell 

 out bv taking in the fluid in whicli they are immersed. 



The ha;matoblasts 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 vears old and somewhat broken down in health. In his 

 case the ha:matoblasts were abnormally numerous, amounting, on 

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

 pu.scles. 



