716 
Transactions of the Society. 
some of the progressive stages, up to what was regarded as a device 
for continuing the species under adverse conditions ; but the material, 
or serous liquid in which the Spirillum was found was so unsuite 1 
for obtaining satisfactorily sharp figures that I determined, secondly, 
to try the pencil and camera lucida, using the same objective, a Leitz 
1/12 horn. im. and an Abbe achromatic condenser, as more likely to 
afford a better chance for depicting the appearances. Then two 
photographic prints were made of the drawings, Nos. 1 and 2 ; No. 1 
containing the same objects as shown in the photomicrographs, whilst 
No. 2 contains similar objects which were not firstly photographed ; 
therefore they are intended simply as additional evidence of the simi- 
larity to those photographed. The drawings were all made at 1000 
diameters, the .photomicrographs at a somewhat less magnification. 
In making the photomicrographs the Zeiss projection ocular was used, 
but the photographic print No. 1 , a , c, d , d 1 , f was taken at about 
half the magnification ; also in making the drawings of some of the 
same objects c, d, d 1 as are in that print they were, for the sake of 
convenience, transposed. The purport of this double method has 
been to furnish proof by comparison that my utmost care was given 
to render the drawings correctly ; only they were not always made at 
exactly the same point of focus as in the photomicrographs, as by 
slight variation such points as were not quite evident in the latter 
could be indicated ; hence some characteristics may in either case 
slightly differ. 
The period at which the preparation was taken was rather a 
peculiar one. The organisms appeared mostly in groups or colonies, 
sometimes surrounding a single or several infusoria, passing through 
three or more up to colonies of a considerable number, as seen in the 
photomicrograph marked No. 3, which was scarcely of the medium 
size ; single individuals were somewhat rare, and these, whether 
consisting of a single joint or comma, or of several in union, were 
noticed to be either quiescent or motile and provided with flagella ; 
therefore it seems to me we can scarcely consider the changes to 
which reference will immediately be made as entirely due to degene- 
ration causes. 
Taking a single joint with two flagella in the early comma stage 
or slightly beyond it, as in the figures of No. 1, lettered a and b, the 
organism appears as possessed of i homogeneous or very faintly 
granular plasm, often at the ends showing a bright or dark nuclear 
spot or spots according to focus, surrounded by a pale halo, and at 
the body side having a fine dark margin ; while, generally, some- 
where in the body of the plasm on either side of the centre a bright 
dark granule or a minute clear spot could be detected. Sometimes a 
broken line of fine granular matter could be traced through the central 
length of the organism, as in No. 2 b 2 , and at a later stage some could 
be found where the organism showed one or more bright lines across 
the width of the body, marking where segmentation would occur, No. 
