. Morphology of gymnosperms. Gymnosperms; Plant morphology. CONIFERALES (PINACEAE) 299 DuCHARTRE (5) and Dangeard (36), the former calling attention to the inconstancy in the number of the cotyledons of polycotyledonous forms, and to the lack of any direct relation between these numbers and the connecting vascular strands. Sachs (27) and Masters (34) opposed this view, and so opinion has long been divided. Hill and De FRAEsnE find that among the Taxaceae and many Cupressineae the cotyledons are definitely two, each (except in podocarps) with a single vascular strand, and the root is diarch fro
. Morphology of gymnosperms. Gymnosperms; Plant morphology. CONIFERALES (PINACEAE) 299 DuCHARTRE (5) and Dangeard (36), the former calling attention to the inconstancy in the number of the cotyledons of polycotyledonous forms, and to the lack of any direct relation between these numbers and the connecting vascular strands. Sachs (27) and Masters (34) opposed this view, and so opinion has long been divided. Hill and De FRAEsnE find that among the Taxaceae and many Cupressineae the cotyledons are definitely two, each (except in podocarps) with a single vascular strand, and the root is diarch from the first. Among the Abie- tineae, in which there are three to many cotyledons, the vascular strand is single and the primary root structure is diarch, triarch, tetrarch, etc., the number of protoxylem poles bearing no obvious relation to the number of cotyledons, and variations oc- curring in the same plant. This lack of relationship between the number of cotyle- donary strands and of root poles was noted by Chauveaud (68), who found in Pinus maritima such combinations as five coty- ledons and a pentarch root, seven cotyledons and a tetrarch root, etc., the cotyledons in general being more numerous than the root poles. The argument further appeals to the occurrence of partially split cotyledons {Cupressus torulosa, Abies sibirica, Pinus montana gallica, Araucaria Cunninghamia), and to the fact that the cotyledons are often obviously in groups. Cases of transition are also cited, in which the strands are more or less divided, and this is accompanied by division of the cotyledon. As an illustration of this, three entire cotyledons were found in Pinus contorta Murrayana, one of which was much larger than the others and contained two separate strands, the conclusion being that one cotyledon had split into two and the other had remained entire. In the case of the higher numbers of cotyledons,. 370 Figs. 369, 370.—Cephalo- taxus Fortunei: fig. 369, proembryo stUl within the egg;
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