io Lawson. — The Gametophytes , Archegonia , Fertilization , 
in the division of the macrospore mother-cells has never been actually 
observed in any of the Conifers. It was hoped that, as the spindles were 
found, some light might be thrown upon this most important step in the 
life-history of Sequoia , but after the examination of the chromatin, all such 
hope was lost. The spindle of the reduction-division was found in several 
preparations, but the chromosomes were too many to allow of an accurate 
estimate of their number. To add to the difficulty, the chromosomes were 
in the form of large V-shaped structures. The arms of the V were very 
long, and when at the equator they extended almost to the poles of the 
spindle. It also invariably happened that several of the chromosomes 
overlapped their neighbours, making it almost impossible to observe the 
method of splitting and separation. It was interesting to note, however, 
that as the daughter-chromosomes approached the poles of the spindle 
they were very much smaller than the mother-chromosomes at the equator ; 
this condition, however, was also observed in the divisions during the for- 
mation of the prothallium and also in the young sporophyte. Although 
the actual reduction could not be observed in the division of the macrospore 
mother-cell, we shall point out later that the number of chromosomes in 
the prothallium and in the development of the archegonium is obviously 
half that in the embryo. Reduction-spindles are shown in Fig. io. 
Soon after the macrospores are formed, they surround themselves with 
distinct walls and almost immediately begin to germinate. The germination 
is first noticeable by a slight increase in the size of all of the spores. This 
increase in size is always accompanied by a division of the nucleus, so that 
each of the ten or twelve germinating spores or female prothallia has two 
free nuclei in its cytoplasm. Their further growth is apparently at the 
expense of the sterile tissue in which they lie imbedded. The cells in this 
tissue, in contact with the young growing prothallia, show every sign of 
disorganization ; the nuclei appearing as homogeneous deeply staining 
masses lying in the distorted and more or less fragmented cells. At this 
stage (Fig. n) there are about eight or ten layers of sterile cells between 
the uppermost macrospore and the apex of the sporangium. The majority 
of the young prothallia show no further development after the first nuclear 
division, but two or three of them continue to elongate, and their increase 
in length is always directed toward the chalaza. Such a condition is shown 
in Fig. ii. Here eight young prothallia are represented, five of which 
have grown but very little, while the remaining three are many times the 
size of the original spores. The smaller prothallia function no farther, and 
are probably absorbed by the growth of the larger ones. Of the two or 
three larger prothallia represented at this stage, and which continue their 
growth down through the nucellar tissue, one grows more rapidly than the 
others, and for convenience we will speak of it as the primary prothallium. 
The one or two remaining prothallia persist in their further development, 
