Henfrey, on Chlorosphcera. 
27 
history seems very varied^, and our information in regard to 
them is at present only fragmentary. Some of the cells 
increase in size^ and always present dense green contents 
like the parent^ finally dividing in the same manner. Others, 
apparently diseased, enlarge without any increase of con- 
tents, going on sometimes even to the formation of a sep- 
tum. In other cases the contents become converted into nu- 
merous small spherical corpuscles, with well-defined outlines ; 
but we believe these again dissolve into a finely granular 
mass before division. But the conversion of the contents 
into a smaller number of larger corpuscles (fig. 7) is, we 
are inclined to think, the first stage of the production of a 
very remarkable structure in the interior of the cells. In the 
cases referred to, the contents lose their green colour, and 
accumulate in rounded masses in the centre of the cell. 
After a time these rounded masses become encysted, and 
each of them sends out a tubular process, which finally 
pierces the membrane of the parent-cell, and opens ex- 
ternally (figs. 11 and 12). They exhibited granular bodies 
around their open orifices; — whether these had been 
motile corpuscles discharged into the water we cannot say, 
but these structures are clearly the same kind of body as 
Carter has described and figured in Spirogyra,^ and which 
Pringsheimf has recently described as a species of parasitic 
Algse allied to Achlya, under the name of Pythium ento- 
phytum. 
At the same time with the preceding were found other 
cells, with the discoloured and almost exhausted contents 
accumulated at one side against the waU of the parent-cell; 
while outside, apparently communicating by an orifice, ad- 
hered a mass of little urceolate bodies (figs. 13 and 14), 
which seem to correspond in character with the structures 
described by Braun under the name of Chytridium. Some 
of these were closed at the attenuated ends, others with the 
neck widely opened. 
If we follow the German algologists, both the internal 
long-necked, flask-shaped bodies, and the external urceolate 
bodies, will be regarded as distinct parasitic bodies. But 
there is much to lead to the suspicion that the internal and 
external bodies, in spite of their different forms, have a 
common origin, and are individualised portions of the contents 
of the Chlorosph(sra-ce[\.j encysted in different ways accord- 
ing as the formation of their coat takes place before or after 
* "Annals of Nat. Hist.,' pi. ix, ser. 2, vol. xvii, p. 113. 
t Pringsheim, ' Jahrb. f. wiss. Botanik./ vol. i, p. 287, 1857. 
d § 
