Thuja.—In the hope of settling these points in some member of 
the Cupressineae, young ovules of Thuja orientalis were collected 
and sectioned in Bonn. The megaspore mother-cell soon becomes 
evident among the conspicuous spongy tissue. It has thicker walk 
and is also less dense than the cells around it. Its position is not 
always in the center of the spongy tissue, and its long diameter is as 
often as otherwise at right angles to the longitudinal axis of the 
ovule (jig. 13; the arrow shows the direction of the axis of the ovul). 
Occasionally there are two or three mother-cells developed, and in 
such cases they are generally separated by cells of the spongy tissue. 
In fig. 13 the mother-cell nucleus is in synapsis, and in jig. r4 the fits! 
division spindle is shown. There is the same kinoplasmic mass at 
the lower end of the cell as in Larix sibiricat and Taxodium. The 
spindle of the next division was not seen, but the result is shown in 
jigs. 15 and 16. Four megaspores are produced and their arrange 
ment is more nearly that of the typical tetrad than in any other 
gymnosperm in which this stage has been described. After the 
completion of the last division, the spores may be seen packed together 
within the still nearly round mother-cell. They are never in a straight 
row, but are so arranged that in thin sections no more than three 
nuclei appear at once. The mother-cell wall around them also stains 
more deeply than those of the neighboring cells, so that the appear 
ance approaches very closely what is found in the divided mother-cell 
of ferns. None of the spores is conspicuously larger than the others 
and it was not determined which one became functional = 
A peculiar abnormality in the ovule of Thuja orientalis is given 
jig.17. Two separate nucelli are present within the same sporangiu 
and each has the usual sporogenous area. In other cases *W0 “il 
sporangia were found in the same ovule, the sporogenous areas ® 
being distinct. I have a preparation showing the same bed 
in the ovule of Erythronium americanum; the nucellus 1s two 
and contains an embryo sac in each lobe. devel 
Taxus.—Strasburger finds’ several megaspore mother-cells 
oped, and says that one or more of them divide into three. 
Jahrb. Wiss. Bot 
4 Jur, H. O., Beitrage zur Kenntniss der Tetradentheilung. 
35:626-659. pis. 15-10. Igoo. 
5 Die Angiospermen und die Gymnospermen. 1879. 
es 
7 
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210 . BOTANICAL GAZETTE [serait 
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