. Botany for high schools and colleges. Botany. 804 BOTANX. reviewing the subject, affirms that the actual development of a gonidium from the end cell of a hypha has not been ob- served. Nylander even goes so far as to declare that in no case do the filaments themselves give birth to gonidia, but that they "have their origin in the parenchymatous cortical cells which are observed on the prothallian filaments of ger- ;* 401.âThe recent observations of Dr. Minks, f if con- firmed, will put to rest the question as to the origin of go- nidia. He studied the small green cells som
. Botany for high schools and colleges. Botany. 804 BOTANX. reviewing the subject, affirms that the actual development of a gonidium from the end cell of a hypha has not been ob- served. Nylander even goes so far as to declare that in no case do the filaments themselves give birth to gonidia, but that they "have their origin in the parenchymatous cortical cells which are observed on the prothallian filaments of ger- ;* 401.âThe recent observations of Dr. Minks, f if con- firmed, will put to rest the question as to the origin of go- nidia. He studied the small green cells sometimes called mi- crogonidia, and makes the announcement that they originate in the interior of the cells of every portion of the lichen- thallus, viz., the cortical and medullary cells, the paraphy- ses and young asci, and. 4, even the spores spermatia. The proto- plasm in the cells forms an axial column, which becomes broken up into rounded bodies of a pale greenish color; these finally become covered Pig. 211.âSoredla of Us-nea barbata. A, sore- by CcU-Walls, and after- diam, consisting of one gonidium covered witli j oonona -fvi-iTvi +Tiq hyphoe; A of many gonidia formed by division ; WdlU tibCdpt! ijoiii uue C, the gonidia separated by hypliffi ; Z) and £â , the ,Tir>+>iov poll n« froo mi Boredia developing into new Ticlien plants. X moiner-ceii dS II ee mi- crogonidia. He asscrts that intermediate forms of all degrees are to be met with be- tween microgonidia and gonidia. Dr. Muller,in making simi- lar observations, arrived at the same conclusion J as to the origin of the microgonidia. The third view as to the origin of gonidia is so intimately connected with the question of the real nature of the gonid- mm and its functional relation to the hyphse, that it can only be explained by taking these into consideration. * In Flora, 1877, p. 256, as quoted in Revue Mycologique, p. 4,1879, and in "Grevillea," 1879, p. 91. \ For a
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