THE ASEPTIC CULTIVATION OF MYCETOZOA. 65 



The writer has seen them divide after the manner described 

 by Famintzin and Woronin (see fig. 13). 



Microscopical Appearance of the Plasmodia and 

 the Structure of the Nuclei. 



Cultures made in fluids without the presence of hay offer 

 the best facilities for studying the plasmodia. The smaller 

 Plasmodia are usually found lying in or upon a clump of 

 microcysts and bacteria. The larger plasmodia can be seen 

 spread out on the bottom or sides of the flask. The closeness 

 of the network, the size of the branches, and the peripheral 

 arrangement of the network can be studied. 



For microscopical study, the plasmodia, with a few drops of 

 the fluid in which they grow, are placed on a slide by means 

 of a pipette. A cover-glass is carefully laid on, and is supported 

 by small bits of wax at each corner to prevent injuring the 

 plasmodia by pressure. The specimen can be immediately 

 examined, and then placed in a moist chamber for twelve to 

 twenty- four hours, after which it may again be examined. 



If it is desired to preserve the specimen, the plasmodium 

 can be fixed and iiardened on the slide and stained by any of 

 the usual methods. Hardening in picric and acetic acids, and 

 then staining in picro-carmine, give good results. 



Fig. 6 represents a segment of a plasmodium taken from a 

 culture of Stemonitis A. Some of the clumps containing 

 microc} sts, bacteria, and plasmodia were placed on a slide. The 

 specimen was examined at the expiration of an hour, and a 

 number of rather long, finger-like, blunt, unbranched proto- 

 plasmic processes were seen radiating from the periphery of 

 the clumps. At the expiration of twenty-four hours the 

 clumps were surrounded by a network of protoplasmic branches. 

 The primary trunks are large, and extend from the clump 

 toward the periphery of the network. They anastomose with 

 each other, and are also connected by means of a finer network 

 of secondary fibres. At the periphery of the network are 

 irregular, angular, flattened, protoplasmic expansions, which 

 at times unite and form irregular plates, as shown in the 



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