. Morphology of angiosperms (Morphology of spermatophytes. Part II). Angiosperms; Plant morphology. THE FEMALE GAMETOPHYTE 95 very heavy integument. They have been noted, for example, in Campanula, Jasminum, and Salvia (Guignard 1Z), and in almost all the species of Compositae investigated. In Calendula lusi- tanica Billings 10° reports a very conspicuous synergid hausto- rium, the synergids developing into the micropyle and much enlarging. Synergid haustoria have been reported in other forms, which are probably outgrowths of the sac. The behavior of the synergids of Trapella, as described by
. Morphology of angiosperms (Morphology of spermatophytes. Part II). Angiosperms; Plant morphology. THE FEMALE GAMETOPHYTE 95 very heavy integument. They have been noted, for example, in Campanula, Jasminum, and Salvia (Guignard 1Z), and in almost all the species of Compositae investigated. In Calendula lusi- tanica Billings 10° reports a very conspicuous synergid hausto- rium, the synergids developing into the micropyle and much enlarging. Synergid haustoria have been reported in other forms, which are probably outgrowths of the sac. The behavior of the synergids of Trapella, as described by Oliver,21 is re- markable, after fertilization increasing much in size, and in the mature seed forming a conspicuous tubercle-like body (Fig. 32). It has been generally assumed that the polar nuclei fuse as soon as formed, which is perhaps generally true. If the time of fusion be related to the act of fertilization, however, it will be found to vary from before pollination to long after fertiliza- tion, and in some cases, already mentioned (Lemna, Gymnade- nia, Balanophora, Anlennaria alpina), the polar nuclei seldom if. Fio. 44 — A, Salixpetiolaris, upper end of embryo-sac Boon after fertilization : p, pollen- tube ; s, synergid : the synergids, which are beaked and have the " filiform appara- tus," have broken through the embryo-sae into the micropyle; x 694. B, /->'. glau- cophylla, synergids not disintegrating after the formation of the embryo; polar nuclei have not fused ; x 694.—After ; ever fuse. In this connection it may be noted that there is no antipodal polar nucleus in Limnocharis .(Hall109) and Iielosis (Chodat and Bernard 83). Fusion of the polar nuclei at any time from before pollination, as in Eichhomia (Smith53), to the moment of sexual fusion, as in Lilium, may be regarded as normal. Later fusion of the nuclei has been noted in the. Please note that these images are extracted from scanned page images that may have been digita
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