. The Canadian field-naturalist. 1994 Mann: Tolypella (Characeae) in Insular Newfoundland 299. Figure 2. Pools from which Tolypella glomerata was collected. The edge of the road berm is visible on the left of the photograph. total height from attached germinated oospore to the tip of the terminal process of up to 16 cm (Figure 3A). The protonematal whorl consists of unbranched sterile branchlets from among which arise axes ter- minating in compact elongate "heads", each head composed of 4-6 whorls of fertile branchlets. These axes producing the fertile branchlet whorls are con- sider
. The Canadian field-naturalist. 1994 Mann: Tolypella (Characeae) in Insular Newfoundland 299. Figure 2. Pools from which Tolypella glomerata was collected. The edge of the road berm is visible on the left of the photograph. total height from attached germinated oospore to the tip of the terminal process of up to 16 cm (Figure 3A). The protonematal whorl consists of unbranched sterile branchlets from among which arise axes ter- minating in compact elongate "heads", each head composed of 4-6 whorls of fertile branchlets. These axes producing the fertile branchlet whorls are con- sidered to be the sexual phase of the thallus as opposed to the protonematal phase described above. Many of these sexual axes are produced at the pro- tonematal whorl, often from six to fifteen and some- times more. Axes of the fertile shoots were relatively short, up to 5 cm, but mostly shorter, producing a cluster of compact heads. Usually only the primary protonema undergoes rapid growth after germina- tion, the accessory protonemata remain smaller (pos- sibly some of them abort?) until the primary one is producing mature oospores. In most charophytes the vegetative sexual phase grows vigorously from the protonematal node, obvi- ous vestiges of the protonemata are soon lost, and eventually fruiting structures are produced. In at least this species of Tolypella, the vigorous rapid growth of the protonemata and the maturing of Oospores while the sexual axes are still relatively immature reveals a neoteny adapted for rapid repro- duction in temporary situations or those where favor- able growth conditions are transient. Such is the habitat in which this species was located in Newfoundland and literature citations also indicate the species as one of ditches, pits, pools, semi-per- manent puddles, in fresh and brackish waters, fre- quently coastal (Groves and Bullock-Webster 1920; Olsen 1944; Moore 1986). Moore (1986) notes that T. glomerata can develop rapidly from germination to oos
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