Botany and Zoology. 113 
ie be so, having seen them open at the summit and emit a great number of 
me free-moving corpuscles (spermatozoids), many of which found their way 
into the now open orifice of the protuberance which contains the forming 
trates the protoplaiie and so is ‘ietoded within ha ell-m is un- 
certain; but Pringsheim thought it was the case, from Seuvite dakota a 
colorless cor puscle like one of the spermatozoids inside of the membrane. 
Next Pringsheim demonstrated a similar feeundation in Cdogonium. 
His results, briefly published in the Proceedings of the Berlin Academy, 
and thence translated into French and English, are now given in detail in 
the first part of his Jahrbiicher, noticed above dogonium consists of 
a row of cylindrical cells. Some of these cells, usually shorter than - 
rest, become tumid, and, without conjugation, have their whole 
contents transformed into a dares a Pringsheim has ascertained int 
their sabia rip cag -. office, he names rat hear : these esca 
of 
androspores fix themselves by the smaller end upon the surface of the 
cell in which a large ordinary spore is forming, or in the vicinity, and 
germinate there, growing longer and narrower at ‘the point of attachment, 
__while near the free end a cross partition forms, and sometimes another, 
co one or two small cells; this is the — persis for pba it a 
Goce ohn (see nn. Sci. . 4, vol. 5), the spore 
: directly dorianp into the normal or caishenia plant. Instead of this, 
; y an alternation of generations (to at ae dnt an ee 
the spore proceeds to convert its contents by successive division into a 
number of zoospores, different from the androspores, viz. small, ra or 
_ oblong bodies, furnished with two long cilia on a short beak at one end, 
_ and for a time moving actively about by their vibration. Coming to rest 
these zoospores germinate, by elongation and the formation of transverse 
haere tes acak: thread-like — ee of a row of Cah a 
