A 



708 SPECIAL HISTOLOGY. 



at all events under the former reagent, the nuclei not unfrequently are 

 farther disintegrated, and fall into irregular, jagged, and constricted 

 corpuscles, or are even resolved into a greater number, 4, 5, 6, and 

 more, of smaller granules, assuming, at the same time, a yellow color, 

 whilst the cell-membranes gradually disappear. The other reactions of 

 these colorless blood-corpuscles are those of the common indifferent 

 cells, and as regards their number, it is, compared with that of the 

 blood-corpuscles, very small, though not always the same, being depen- 

 dent upon the energy with which nutrition is going on, and therefore 

 more considerable when a large quantity of chyle has entered the 

 blood after a full meal. It is impossible to give any definite statement 

 as to their number, without perfectly accurate enumeration ; but this 

 much is certain, that the usual statement, that there is one colorless to 

 every ten colored blood-corpuscles, is quite incorrect. I find, with 

 Henle and Donders, that they are much less numerous than this, and am 

 of opinion, that when the latter, with Moleschott, reckons 5'1 colorless 

 to 2000 colored corpuscles, he is not far wrong. After meals, these 

 authors found the number of the latter augmented to 6*2, whilst in 

 fasting animals, as was also noticed by Heumann in Pigeons, they 

 diminished in number ; and after long fasting, at least in Frogs, they 

 saw them disappear altogether.* Their increase after venesections, not 

 only relatively but even absolutely, is a very remarkable circumstance; 

 and this, as in the Horse, a'fter very copious abstraction of blood (as 

 much as 50 Ibs.) may proceed to such an extent, that the colored and 

 colorless corpuscles appear to exist in equal numbers. The white cor- 

 puscles are lighter than the colored, and they are consequently more 

 numerous in the upper strata of the crassamentum. When the latter 

 presents a buffy coat, it always contains a great number of these cor- 

 puscles, and especially if their number has been augmented by previous 

 venesections, so as in such cases to constitute even half of the bufty 

 coat (Remak, Donders). Their less tendency to subside is, moreover, 

 increased by the circumstance, that although they have an uneven sur- 



* [Moleschott has recently continued his researches on the relative number of the white 

 and the red corpuscles, and has arrived at some interesting results. In boys from 2- to 12 

 years of age, he found as the mean in seven enumerations of the corpuscles, 4 - 5 colorless to 

 1000 colored; in adults from 21 to 49 years, 2'9 colorless to 1000 colored ; in old men from 

 62 to 78 years, 2'6 colorless to 1000 colored. In women from 14 to 38 years the average 

 was only 2-6 colorless to 1000 colored corpuscles, whilst in the blood of the same women 

 while menstruating, he counted 4 colorless to 1000 colored. An increase of the proportion 

 of the colorless corpuscles was also observed in pregnant women (3'G colorless to 1000 

 colored), and in the blood of persons after meals which were rich in albuminous sub- 

 stances. After having partaken freely of the latter, he noticed in his own case 3'5 color- 

 less to 1000 colored corpuscles, whilst a few hours after a breakfast on non-albuminous 

 substances, he counted only 2'1 colorless to 1000 colored corpuscles. These observations 

 of Moleschott are important, and must be borne in mind in determining the number of the 

 colorless corpuscles in suspected cases of leucocythemia. DaC.] 



