98 DE BARY, OX THE MYCETOZOA. 



Tr i chin, the author observes, that the only correct account of 

 their structure is that given in this Journal in October, 1854, 

 and April, 1857. 



In the third part, an account is given of the formation and 

 development of ALthalium septicum, and one of the principal 

 arguments in favour of the animal nature of the Myxogasteres 

 is grounded upon the supposed fact that the creeping threads 

 of mucilaginous matter, by the confluence of which the fruc- 

 tifying mass of iEthalium is formed, consist of sarcode. The 

 author says — " The main substance of the threads is formed 

 "of that structureless, colourless, transparent, half-fluid 

 " matter, called by Dujardin, sarcode, aud by Ecken, shapeless 

 " contractile matter. 



"The principal peculiarity of sarcode, viz., its high degree 

 " of independent contractility, is very remarkable in the sub- 

 " stance of these threads. It exhibits continual changes of 

 " form and fluctuating motions, such as are known to occur 

 " in the bodies of the Khizopoda. 



" Its chemical nature also agrees essentially with the sar- 

 t( code of the lower animals. The rose-red colour produced 

 " by sugar and sulphuric acid, and by Millon's test, and 

 " the brown colour produced by iodine, testify to its nitro- 

 " genous nature. It contracts and hardens in alcohol and in 

 11 nitric acid, and becomes pale and transparent in acetic acid, 

 " without however becoming dissolved. On the other hand, 

 " it dissolves in liquor ammonia?, in solution of caustic potass, 

 " even when very weak, and in solution of carbonate of 

 " potass." 



The spore-cases of all Mycetozoa are stated to be formed 

 of sarcode threads, essentially like those of sEthalhon. Dr. 

 de Bary has noticed in JEthalium septicum, as well as in 

 Didymium serpida, and in a species of Physarum that when 

 the moisture is allowed to evaporate very slowly, and (spe- 

 cially at a low temperature, the threads break up, by con- 

 traction, into irregularly shaped bodies, which, as the 

 desiccation continues, assume a waxy or horny consistence. 

 The Avholc substance of each of these bodies again suddenly 

 breaks up into numberless globular or oval cells, sur- 

 rounded by a double-outlined membrane, which exhibits, 

 under iodine and sulphuric acid, or under Schulze's solution, 

 active and intense cellulose reaction. All these cells in a 

 mass are imbedded in a homogeneous hyaline substance not 

 exhibiting cellulose reaction. This substance 4 is more 

 strongly developed at the outer surface of the mass of cells. 

 It softens in water, so that the cells can be separated by 

 pressure, and then surrounded by a thin layer of the inter- 



