Dr. BealEj on the Red Blood-corpuscle, 89 
tides resulting from the division of red blood-corpuscles 
(PL VII^ fig. 9). As this change occurs immediately blood 
is drawn^ and in many instances has taken place before suffi- 
cient time has elapsed for the specimen to be placed under 
the microscope^ and seems to affect the youngest corpuscles, 
it seems to me very probable that it is to be explained by the 
tendency to form processes which germinal matter often 
exhibits when stationary. It will be shown presently that 
many of these small^ and probably younger_, corpuscles con- 
tain germinal matter. A somewhat similar phenomenon is 
observed in the case of white blood-corpuscles, and also in 
the lymph-corpuscles. 
In connection with this question of crystallization of the 
blood-corpuscleSj I would remark that when water is added to 
blood- corpuscles they swell, but they do not burst, as is gene- 
rally stated. They become very transparent, and doubtless a 
certain quantity of the fully formed colouring matter is dis- 
solved out ; but as the water evaporates, the corpuscles again 
assume their ordinary characters, the only change in many 
being that they are paler than before. 
When crystallization commences in Guinea-pig's blood after 
treatment with water, individual corpuscles may be seen to 
assume the crystalline form, as in specimens to which water 
has not been added. The material which crystallizes is ca- 
pable of being dissolved in water, but it is not very readily 
soluble. 
On the nature of the oval blood-corpuscle of the frogj and of 
the changes occurring during its formation. 
The same facts to which I have adverted in several 
papers may be observed in the case of the oval red blood- 
corpuscle of the frog. Within is the mass of germinal mat- 
ter, usually termed the nucleus. This, like all matter corre- 
sponding to it (living or germinal matter) , is perfectly colour- 
less, but becomes coloured by the carmine solution. The outer 
part, which is naturally coloured, is not coloured by the car- 
mine solution. This, therefore, is the formed material which 
was once in the state of germinal matter, and was capable of 
producing matter like itself, and of being resolved into coloured 
formed material. But this formed material, being once pro- 
duced, cannot form matter like itself, although it can be 
changed, dissolved, and converted into other substances. It 
is the seat of physical and chemical actions alone. Vital 
changes are restricted to the germinal matter. 
The young blood-corpuscle, like the young elementary part 
