444 



Mr. L. (). Grocock said the group was named Mycetozoa, in 

 1858, by De Baiy, who then thought that amoeboid movement 

 was peculiar to the animal kingdom. Ten years later, however, 

 he was forced to admit that it was common to both animals and 

 plants. Most authorities now, especially abroad, preferred the 

 term Myxomycetes. For continuous observation the speaker 

 preferred a modification of the "hanging drop" method described. 

 He took a glass ring about 1| in. in diameter and 1 in. in height. 

 This, cemented to a slip, was filled about three-quarters full with 

 water and the " hanging drop " placed above. Care had to be 

 taken to sterilise the water ; but food material must be provided 

 for the spores. He had found fragments of gum very good ; he 

 had some recollection of a plate in a very old number of Science 

 Gossi]) illustrating a fossil form of the group from the coal measures. 



A visitor, Mr. J. M. Coon, asked, by permission of the President, 

 if Mr. Hilton had considered the nuclei of the Mycetozoa. They 

 are described as of three sizes — very large, medium, and small 

 " nuclear bodies." The two former are generally only described 

 as " nuclei," and the latter " nuclear bodies." He had observed 

 these in the plasmodia of Badhamia, Fuligo, and other forms, and 

 in the sclerotium and the immature sporangia of Badhamia. He 

 suggested that the larger of these bodies may not be true nuclei, 

 as the chromatic material is so regularly distributed within the 

 membrane, and he had not yet observed it condensed, as is usual 

 in the resting stage of nuclei, and as it is in the case of the two 

 smaller nuclei. Neither had he observed in the case of the larger 

 " nuclei " the mitotic spindles of nuclear division, whereas in 

 respect of the middle size nucleus he had seen very large numbers, 

 and, speaking with reserve, he thought he had also observed it in 

 smaller nuclei. He had never seen the chromatin material in the 

 larger bodies condensed to an equatorial plate nor forming 

 "asters," but had occasionally observed an appearance as of open 

 chromosome loops. Mitosis for spore formation appears to take 

 place some hours after the forming of sporangia, and previous to 

 the colour of the sporangia changing from that of the plasmodium. 

 With regard to the cultivation chamber, he suggested moss spread 

 on the bottom of a glass dish as an alternative which had several 

 advantages. 



Journ. Qcekett Microscopical Club, So: 2, Vol. IX., No. 50, November 1906. 



