338 SPECIAL HISTOLOGY. 



pale needles, columns, and plates, probably belonging to the 

 rhombic system (Funke), and also tetrahedral (in the Guinea 

 Pig, Lehmann, Funke), and are characterised by their little per- 

 manency, since they perish in the air, are very soluble in water, 

 and also in acetic acid, alkalies, and nitric acid. Those found 

 by me in the blood of the Dog resisted the action of water, 

 but I do not think that they were of a different nature, and 

 I should be inclined to refer this difference to the greater re- 

 sistance of the blood-globules themselves. Funke believes that 

 they consist of the albuminous contents of the blood-cells in 

 combination with hematin, relying, for support to this opinion, 

 especially upon their numbers, their occurrence in blood-cells, 

 their formation, as observed by him, from aggregations of blood- 

 cells, and their absence from the serum of the blood ; but I 

 cannot regard this hypothesis as at present fully established, 

 and it appears to me that further proof is required before we 

 should admit the existence of crystals from the substances in 

 question, and the more so, because colourless crystals are also 

 formed in the blood, quite independently of the blood-cells. 

 Robin and Verdeil, moreover, assert that they have also 

 obtained crystals from the serum of the blood ; and the quantity 

 of the crystals is by no means opposed to the notion that they 

 are derived from a salt of the blood merely tinged with hcematin, 

 since, in the case of fibrin we see that not much of a substance 

 is required to occupy a large space.] 1 



1 [Reichert was the first to drawattention to the occurrence and nature of crystallised, 

 albuminous matters coloured with haematin, in his ' Beobachtungen iiber eine 

 eiweissartige Suhstanz in Krystallform,' Miiller's 4 Archiv,' 1849. These were tetra- 

 hedrons of as much in some cases as T ' 5 "' long, and occurred upon the placenta and 

 foetal membranes in a Guinea Pig. Their albuminous nature was confirmed by 

 Schmidt and Buchheim ; subsequently, ' Bericht,' Miiller's 'Archiv,' 1852, Reichert 

 states that he has again found the crystals in the same locality, and that he has 

 convinced himself, by further experiments, that the difference observed between his 

 crystals and those described by Kunde and Lehmann, arose entirely from the action 

 of the spirit in which his first specimens had been preserved. Reichert observed the 

 development of crystals of the same kind, though smaller, in fresh blood taken 

 from the heart of the Guinea Pig. 



In connexion with this subject, Dr. Ayres has recorded a very interesting observation 

 with regard to the occurrence of prismatic, more or less red crystals, in a band of olive- 

 green, almost black matter, having the appearance of coagulated blood at the margin 

 of the placenta of the Bitch (' Quarterly Journal of Mic. Science,' vol. i, p. 299, with 

 figures). See also the papers of Dr. Parkes (' Med. Times and Gazette,' 1852) and 

 of Dr. Sieveking (' Brit, and For. Med.-Chir. Rev.,' 1853) on this subject. — Eds.] 



