BOTANICAL GAZETTE. 257 
tant of these facts together, and verifying them by observations 
on something more than 130 species, has been a task well per- 
-formed by Professor Gay, of the School of Pharmacy at Mont- 
pellier, whose local monograph of the group! is a worthy model 
for monographers elsewhere. 
Aside from the behavior of the nucleus in cell-division, which 
_The same treatment brings out the so-called pyrenoids, 
minute bodies .5-.154 in diameter, which their discoverer, 
ing the grains. A good method for the demonstration of the 
latter is indicated in the employment of acetic acid, in which the 
ch of the proto- 
: and pyrenoids, which 
multiply apparently independently one of the other, the cell is 
general b é : 
“ differentiation of the sexes. From plants which are exclu- 
7 apogamic (Gonatonema, Spirogyra mirabilis), a series 1s 
traced through the Desmids, where similar vegetative cells con- 
2h and the Mesocarpez, where, though still similar, their pro- 
Piasm undergoes a rearrangemen 
Ot. Gay: Bosal ; ‘oni 
“ray: Essai d’une M raphie locele des Conju 
ver he Fils, 1884, 8° 110 oak a : 
West, ime der Algen.—Verh. naturh. Ver. d. preuss. 
guées. Montpellier. 
Rheinl. u 
