PROCEEDINGS OF THE SOCIETY. 169 



The President said lie was sure that the Society would feel very- 

 much indebted to Mr. Cheshire for his paper, which apart from the 

 skill which he had shown in such a remarkable degree in working 

 out the minute anatomy, was valuable on account of its suggestions ; 

 and they would look forward with great interest to its publication. 



Mr. Dowdeswell read a paper " On the Occurrence of Variations 

 in the Development of a Saccharomyces " (supra, p. 16). 



Dr. Maddox said he had examined many forms, but had not met 

 with those mentioned, though he had seen some very similar to them 

 in the case of lactic fermentation. From the extreme care taken, he 

 did not think it was possible to have got it otherwise than pure. 

 In the lactic ferment, the form taken was more pear-shaped, the 

 filament being like a long chain divided in the centre by two eggs. 

 The acetic ferment was somewhat similar, and he would at some 

 future day print some photographs of that form. With respect to 

 the " Comma " bacillus, he might say that he had examined and 

 photographed them, and found that they differed from the cholera 

 bacillus, the latter not being so much curved, but he thought that 

 mere variation in form must not be taken as having any morphological 

 value whatever, though the point was worth mentioning as the 

 cholera bacillus had taken up so much attention of late. 



The President said that for his own part he was quite convinced 

 that it was impossible to study these organisms without finding that 

 they varied under different circumstances. Too much reliance must 

 not, therefore, be placed upon the variations observed. 



Mr. T. B. Rosseter's paper, " On the Gizzard of the Larva of 

 Corethra plumicornis, its structure and uses," was read by Prof. Bell, 

 who referred to the observations of Prof. Lankester, published in 

 1865, and the paper was also discussed by Mr. Beck, Prof. Stewart, 

 and Mr. Crisp. 



Dr. Van Heurck's notes on " Amphipleura pellucida resolved into 

 'Beads,' — Nature of the Striee of Diatoms," was read and the photo- 

 graphs exhibited (see Vol. IV., 1884, p. 971). 



Mr. J. Mayall, jun., said that since this paper was communicated. 

 Dr. Van Heurck had sent another short note upon the subject. He 

 considered he had solved the difficulty of obtaining sharp photographs, 

 believing it to be due to the tremor of the mechanical stage. By 

 placing the object lower upon a very rigid stage, he was able to get a 

 much better photograph. He finds that the longitudinal lines are 

 distinctly coarser than the transverse, and that the alveoli do not 

 exist on the black lines, but that they are between them, so that the 

 space between would, he thinks, be resolved into " beads " if the 

 optical means at disposal were sufficient. In viewing these objects 

 with a vertical illuminator and in Canada balsam, the diatom was 

 practically invisible, but Dr. Van Heurck has found that when 

 mounted in the dense fluid of Prof Hamilton Smith, the object was 



