246 CLINICAL DIAGNOSTICS. 



care not to stretch the skin during the operation. If a larger 

 quantity of blood is desired a hypodermic needle, inserted into 

 the jugular vein, answers the purpose better. [As far as an- 

 noyance of the animal is concerned, tapping the jugular vein 

 is preferable in all cases.] In practice we may limit our- 

 selves to the microscopical examination ; for this purpose a 

 single drop of blood, placed directly on the glass slip or cover, 

 will serve the purpose. From this drop we can make a few 

 cover glass preparations, allow them to dry, take them home, 

 fix, stain and examine them at leisure; or we may add a 0.3% 

 solution of sodium chloride and examine the blood in its fluid 

 condition. Exact blood examinations are difficult and must be 

 carried out with such care and minuteness that the practitioner 

 is obliged to get along with the results of the simplest meth- 

 Fi B . 55. ods. For those who care to take 



.. (~\ a f^^ U P tne study of blood examinations 



A ^ Q in detail we recommend "Jacksch- 



& *W <9J) & Klinische Diagnostik." 



y\ £? fy ,-£. Number of blood corpuscles. 



*~r& ™ O j) n ^^ The absolute number of blood cor- 



sR\/K~* a ^ puscles in a given amount of blood 



^3 c$\ (?) v can only be determined with the 



Abnormal Forms of Red aid of special blood-counting appa- 



corpuscies. ratus (Thoma-Zeiss) . According 



to the investigations of Storch, the number and proportion of 



red and white corpuscles per cubic millimeter are as follows : 



Red Corpuscles. White Corpuscles. Proportion. 



