[Illustration: Fig. 299. Stamen of Globe Amaranth; very short filament bearing a single anther-cell; it is open from top to bottom, showing the pollen within.] [Illustration: Fig. 300-305. Stamens of several plants of the Labiate or Mint Family. Fig. 300. Of a Monarda: the two anther-cells with bases divergent so that they are transverse to the filament, and their contiguous tips confluent, so as to form one cell opening by a continuous line. Fig. 301. Of a Calamintha: the broad connective separating the two cells. Fig. 302. Of a Sage (Salvia Texana); with long and slender connective resembling forks of the filament, one bearing a good anther-cell; the other an abortive or poor one. Fig. 303. Another Sage (S. coccinea), with connective longer and more thread-shaped, the lower fork having its anther-cell wholly wanting. Fig. 304. Of a White Sage, Audibertia grandiflora; the lower fork of connective a mere vestige. Fig. 305. Of another White Sage (A. stachyoides), the lower fork of connective suppressed.] 291. But anthers may become _one-celled_, and that either by confluence or by suppression. 292. By confluence, when the two cells run together into one, as they nearly do in most species of Pentstemon (Fig. 297), more so in Monarda (Fig. 300), and completely in the Mallow (Fig. 298) and all the Mallow family. 293. By suppression in certain cases the anther may be reduced to one cell or halved. In Globe Amaranth (Fig. 299) there is a single cell without vestige of any other. Different species of Sage and of the White Sages of California show various grades of abortion of one of the anther-cells, along with a singular lengthening of the connective (Fig. 302-305). 294. The splitting open of an anther for the discharge of its pollen is termed its _Dehiscence_. [Illustration: Fig. 306. Stamen with the usual dehiscence of anther down the side of each cell.] [Illustration: Fig. 307. Stamen of Pyrola; cells opening by a terminal hole.] [Illustration: Fig. 308. Stamen of Barberry; cells of anther each opening by an uplifted valve.] 295. As the figures show, this is commonly by a line along the whole length of each cell, either lateral or, when the anthers are extrorse, often along the outer face, and when introrse, along the inner face of each cell. Sometimes the opening is only by a chink, hole, or pore at the top, as in the Azalea, Pyrola (Fig. 307), etc.; sometimes a part of the face separates as a sort of trap-door (or valve), hinged at the top, and opening to allow the escape of the pollen, as in the Sassafras, Spice-bush, and Barberry (Fig. 308).