A synopsis of the Characeae'
A synopsis of the Characeae'
A synopsis of the Characeae'
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42 BULLETIN OF THE TORREY BOTANICAL CLUB [Von. 91nata," having <strong>the</strong> tendency for plants to be broad above,mucroniform dactyls, reticulate oospore membrane, nodifferentiation <strong>of</strong> fertile whorls, absence <strong>of</strong> mucus, andabbreviated dactyls. Gioallenia, on <strong>the</strong> o<strong>the</strong>r hand, includesforms resembling <strong>the</strong> European "N. graeilis" withtendencies for plants to be narrowed above, tapereddactyls and end cells, granulate oospore membranes, formation<strong>of</strong> heads, presence <strong>of</strong> mucus.] [Three taxa whichhave mucronate dactyls, and would seem to fit here, areassigned elsewhere: N. tasmanica [Aust, Oc], N. huillensis[Af], and N. doidgeae [Af].]37a. Branchlets uniform in a whorl; homoeoclemous.38a. Gametangia never at base <strong>of</strong> whorl; an<strong>the</strong>ridia140-540 p, in diameter; heads rare; monoeeious(except subsp. fiagelliformis) ..................................................................................... 1(49) Nitella furcata [cosm][includes Macrodactylae and Brachydactylae].38b. Gametangia occasionally at base <strong>of</strong> whorl; an<strong>the</strong>ridialarge (to 600 1.1, in diameter) ; without heads;dioecious ............................. 2(50) Nitella duthieae [Af]38c. Gametangia never at base <strong>of</strong> whorl; an<strong>the</strong>ridia 320-500 .11 in diameter; without heads, but whorlscompact, spheroid and isolated, 0.3-0.5 cm. indiameter; without mucus (4) ; dioecious .................................................................. 3(51) Nitella plumosa [Af]37b. Branchlets in a whorl <strong>of</strong> two kinds, heteroclemous; dioecious.............................................. 4(52) Nitella stephensia [Af]36b. Medium to small; dactyl end cells not mucronate (except N.pseudollabellata var. penicillata), but base <strong>of</strong> end cellabout as wide as distal end <strong>of</strong> penultimate cell, <strong>the</strong> twocell outlines tapering smoothly ............................................................................................................................ Sect. 2(14) GIOALLENIA[A few forms have somewhat mucronate dactyls, but aresmaller plants with upper whorls smaller than <strong>the</strong> lower.]39a. Oospore membrane smooth, granulate, papillate or vermiform,but not reticulate.40a. Medium to large (to 60 cm.) ; some branchlets exceeding5 cm. in length.41a. Upper whorls lax and without mucus, or rarelysomewhat spicate with mucus.42a. Medium sized (20-30 cm.) ; with or withoutcentral secondary branchlet ray ;branchlet furcations variously 2-5-furcate;rarely dioecious .............................1(53) Nitella pseud<strong>of</strong>labellata [Af, As, Aust, Oc]42b. Medium to small (5-15 cm.) ; withoutcentral secondary branchlet ray (exceptsubsp. gracillima [As]); 1-3-furcate;monoecious or dioecious ......................................................... 2(54) Nitella gracilis [cosm][includes two pluricellulate taxa, subsp.lechleri [SA] and subsp. zeyheri [Af]].42e. Robust (to 60 cm.) ; axes 1000 la in diameter;dioecious.43a. Dactyls 2-3-celled .............................................................. 3(55) Nitella remota [Aust]43b. Dactyls (1—)2-celled .................................