214 
Atkinson. — A Monograph of the 
branched, moniliform chains on the interior of the sexual 
shoot. Developed as lateral shoots from the Chantransia- 
form, of a greenish, yellowish-olive, violet or purple color, 
sometimes changing color in drying. Annual. 
Protonema . Chantransia- form of erect, branched, confervoid 
filaments of limited apical growth, not producing gonidia, 
greenish or violet, developed as lateral shoots from the pros- 
trate form, rarely from the spores. Autumnal, fugacious. 
Prostrate form, cellular, or with matted creeping confervoid 
filaments, of unlimited apical growth, fixed to the substratum, 
produced from the spores and by growth from the basal cells 
of the Chantransia-i orm. Perennial. 
Habitat , on rocks or wood-work, etc. in fresh-water streams 
at rapids, falls, etc., in turbulent or swift waters. Period of 
development, October to June. 
Genus LEMANEA 1 Bory, Emend. C. A. Ag. 
Apona Adans., Fam. d. Plantes, ii. 1763. 
Polysperma Vauch., Hist. d. Conferves, 1803. 
Chantransia D. C., Flore Frangaise, vi. 1805. 
Lemanea Bory, Ann. d. Mus. Hist. Nat. 1808; C. A. 
Ag. Species Alg. pp. 1-8, 1824-28; Kutz., Species Alg. et 
Tab. phyc. 1849; Rabh., Flora Europ. etc. iii. 1864-68; 
1 The genus Lemanea as established by Bory (in honor of M. Leman, a French 
naturalist) included several species of plants now known under the genus 
Batrachospermum , loc. cit. He might well have emended Polysperma of Vaucher, 
since the Conferva Jluviatilis of Linn, was made by Vaucher the type of his genus 
(see note below) ; or, eveft better, have adopted the Apona of Adanson which 
Desveaux (loc. cit.) regretted he did not do. Bory gives no reason for rejecting 
Apona Adans., but his reason for not adopting Polysperma (loc. cit. p. 178) was 
that Vaucher included in the genus a widely different plant, Conferva glomerata 
Dill. C. A. Agardh (loc. cit.) emended the Lemanea of Bory so as to include those 
forms now regarded as constituting this genus. However great the claims of 
justice may seem to be for Polysperma or Apona , it seems wiser to prevent needless 
confusion by retaining a name which for three-quarters of a century has met with 
universal acceptance, and though in itself inexpressive of any character, yet conveys 
to the minds of botanists the familiar habit of these plants. 
Note. — Bory, as well as some later writers, did Vaucher injustice in thinking 
he had not observed the spores and their germination in Polysperma fluviatilis. 
On the other hand, Bory could find no spores, and erred in thinking the plants 
reproduced by the separation and growth of the papillae ! 
