. A practical course in botany, with especial reference to its bearings on agriculture, economics, and sanitation. Botany. CRYPTOGAMS 337. Fig. 478. — Longitudinal 389. The antheridia. — Examine one of the male recep- tacles on both surfaces and in vertical section. Notice the tiny egg-shaped bodies sunk in little cavities between the lobes just under the upper epidermis (Fig. 478). These are antheridia. When mature, they rupture at the apex, and multitudes of extremely small bodies, called anthero- zoids, or spermatozoids, are discharged from them. 390. Archegonia.—Next examine one of the fem
. A practical course in botany, with especial reference to its bearings on agriculture, economics, and sanitation. Botany. CRYPTOGAMS 337. Fig. 478. — Longitudinal 389. The antheridia. — Examine one of the male recep- tacles on both surfaces and in vertical section. Notice the tiny egg-shaped bodies sunk in little cavities between the lobes just under the upper epidermis (Fig. 478). These are antheridia. When mature, they rupture at the apex, and multitudes of extremely small bodies, called anthero- zoids, or spermatozoids, are discharged from them. 390. Archegonia.—Next examine one of the female receptacles. Look on the under surface, between the narrow divi- sions of the receptacle, for radiating rows of flask-shaped bodies with their necks section of a male receptacle . ,, , in ii of marchantia polymorpha, turned downward, and all surrounded magnified: «, antheridia; by a toothed sheath or involucre (Fig. *,thaUus; «,venfraiscales; ^ ,,. rhizoids. 479). These bodies are the archegonia, or female organs, and correspond, loosely speaking, to the ovaries of flowering plants. If the receptacle is a mature one, the archegonia will be replaced by the ripe spore cases (sporangia), as at /, Fig. 479. Make enlarged drawings of the upper surface of a male and a female receptacle, and of a vertical section of each, passing through an anther- idium in the male, and an arche- gonial row in the female receptacle. Label the parts observed in each. 391. Minute study of an arche- gonium. — Place under the micro- view in the figure; /, a spore scope a very thin, longitudinal section case' through a ray of a receptacle con- taining a young archegonium, and observe that the latter consists of a lower portion, the venter, v. Fig. 480, and an. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Andrews, Eliza
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