16 Dr. John Mailer's Examination of [July 



of fibrin, while 3004 grs. of blood from the carotid artery 

 left 14^ grs. of fibrin. The arterial blood of the goat, 

 consequently, contains 0*483, and the veinous blood 0*395 

 per cent, of dissolved fibrin. The composition of the 

 nuclei is still a matter of uncertainty. They possess the 

 characters, in a chemical point of view, common to coagu- 

 lated fibrin, and to coagulated albumen, for they dissolve 

 easily in alkalies, and with diflftculty in acids. When kept 

 in contact with acetic acid for a day they are not altered, 

 although acetic acid takes up some fibrin pretty readily. 

 In the same acid the globules of the frog's blood are con- 

 verted into a brown powder, which, when microscopically 

 examined, is observed to consist of the nuclei, with some of 

 the colouring matter adhering, while fibrin becomes opales- 

 cent in acetic acid. 



Prevost, Dumas, and Edwards, consider the nuclei of 

 the globules as the elements of the muscular fibres, be- 

 cause they state that the muscular and nervous fibres, 

 according to their observations, consist of aggregated 

 globules. Neither Miiller, however, nor C. A. Schultze, 

 could detect under the microscope, globules in the muscular 

 fibres. The former states, that in the glitter of sun-shine, 

 globules may be seen, as in every texture, but undistin- 

 guishable from the unequality of surface, which is apparent 

 in the nerves and muscles. With regard to the brain and 

 spinal marrow, Miiller could come to no conclusion, because 

 he could obtain no proper medium for examining these 

 structures under the microscope. According to him, the 

 globules of the blood of the frog, are five or six times 

 larger than the primitive muscular fibres of that animal. 

 We estimate the diameter of the fibres of the facial nerve 

 in the calf, at from -000437 to -001023 English inch. The 

 finest fibres, he found by measurement, to be much less 

 than this, and not half as large as the globules of the blood. 

 The fibres of the spinal nerve in the cat when compared 

 with the globules of the blood, amount to about one-third 

 or one-half of their diameter. The nervous fibres of the 

 frog are about one-third or one-half of the human fibres, 

 and one-eighth of the blood globules of the frog. 



The most important materials for nourishment appear to 

 be the albumen and fibrin dissolved in the blood, which 



