16 SPERMATOGENESIS AND FECUNDATION OF ZAMIA. 
four parts water gave very excellent results in fixing the pollen tube 
apparatus. In the fixation of the archegonia, however, at the time of 
fecundation and during the development of the embryos, it is neces- 
sary to use the fixative very strong, as it is difficult for the solution to 
penetrate the starchy matter of the prothallus which surrounds the 
archegonia. 
In staining, the Flemming triple process with safranin, gentian violet, 
and orange G. gave by far the best results and was most ead 
used. Hoidenhain’ s iron-hematoxylin was also used considerably, and 
besides this Czoker’s alum cochineal with Bismarck brown, fuchsin, 
and some other stains were occasionally used for comparison. 
DEVELOPMENT OF THE MICROSPORES. 
The pollen cones (figs. 3 and 4) of the two Florida species of Zama 
begin to appear at the apex of the stem in July and continue to 
develop until the following January, when the pollen is Ce 
and pollination takes place. 
The mature pollen grain examined in water is nearly te ical, but 
somewhat flattened on one side where the prothallial apparatus is 
attached. (Fig. 11.) 
The earliest description of the pollen of Zamia known to the writer 
is that of Schacht (97) in 1860: 
Endlich hat Zamia ein kleines Pollenkorn mit einer sehr tiefen Lingsfalte, welche 
sich in Wasser nicht ausgleicht. (Taf. XVII, F. 26 und 27.) Dieser Falte gegentiber 
liegt die kleine Tochterzelle, welche erst bei sehr gelungenen Querschnitten sicht- 
bar wird (F. 28) und wahrscheinlich wie bei Cupressus nicht zur ssullctong 
kommt, wihrend die grossere sich als Pollenschlauch verlingert. 
In 1872 Juranyi (72) described the structure and development of the 
pollen of Ceratozamia longifolia, which evidently corresponds closely 
with what occurs in Zama. He found that two small cells were regu- 
larly cut off at one side of the large cell, and in some cases three. 
While the different cell stages of development are described and fig- 
ured, the details of the division leading to the formation of the differ- 
ferent cells was not followed. - | 
In his study of the development of the pollen of certain Cycads, 
principally Ceratozamia mexicana, Guignard (45) was unable to con- 
firm Juranyi’s conclusion as to the occasional production of three pro- 
thallial cells. ‘*According to the observations of M. Juranyi,” wrote 
Guignard, ‘ta third small cell may be formed by the division of this 
latter nucleus; but it does not appear to be so in the case of Ceratoza- 
mia mexicana.” * 
1<<T) aprés les observations de M. Juranyi’’ wrote Guignard, ‘‘il peut se faire une 
troisicéme petite cellule, par suite de la division de ce dernier noyau; mais il ne pa- 
rait pas en étre ainsi dans le Ceratozamia mexicana.”’ 
