sporangiophore's Usage Examples:

In the other Calamarian strobili known the whorls of sporangiophores are separated by whorls of bracts.

(All except d represent vertical sections of sporangiophore or sorus.

At the time of sporangial formation the protoplasm with numerous nuclei streams into the swollen end of the sporangiophore and there becomes cut off by a cell-wall to form the sporangium.

Such may be termed sporangiophores.

The stamens of Araucaria and Agathis are peculiar in bearing several long and narrow free pollen-sacs; these may be compared with the sporangiophores of the horsetails (Equisetum); in Taxus (yew) the filament is attached to the centre of a large circular distal expansion, which bears several pollen-sacs on its under surface.

The recently discovered species, Sphenophyllum fertile, while resembling Bowmanites Romeri in its peltate, bisporangiate sporangiophores, is peculiar in the fact that both dorsal and ventral lobes of the sporophyll were fertile, dividing in a palmate manner into several branches, each of which constitutes a sporangiophore.

A, B, Section of Leaf of Potato F, G, H, J, Further development with sporangiophores of Phy- of the sporangia.

The overlapping bracts afforded protection to the sporangia, which were borne on sporangiophores springing from the upper surface of the coherent bracts near their origin from the axis; two sporangiophores usually arose from each bract, and sometimes adhered to its upper surface for some distance.

This similarity is closest in Archaeocalamites, an ancient type found in Upper Devonian rocks; in this the strobilus consists of peltate sporangiophores inserted in whorls on the axis.

From each segment, near its base, a stalked peltate sporangiophore arose; this bore four sporangia, which hung parallel to the stalk.

That these three sterile segments, with their sporangiophores, are together comparable to one of the bracts of Sphenophyllum, with its sporangiophores, is shown by the vascular supply in each case being derived from a single leaf-trace, So far as is at present known, the Sphenophyllales were homosporous.

Synonyms:

stem, stalk,

Antonyms:

rear, ride,