Show tho the life history of au ali alga interest lit of R reproduce tion of 1 7 r the thel meeting of the san fran cisca ad society on oil wednesday evening was the most interesting of tho the j year ear there was a i good atten attendance darme of members rs an and d dr bre fogle of san francisco as yi visitor the periodical table was well filled with tho the late latest st scientific publications and the demonstration able va covered with a group of instruments each with objects illustrating tho the subject tt prepared for the evening 9 study the life history of Fati cherl a which was A described e scribe b by A H U who lias lim given much time fo to tho the study or ot this humble plant dr S M moeace vice Vic dent occupied the chair A communication muni cation from the Y M 0 A was read asking the society ety kohold 0 hold a i reception in connection with a course of lectures arran arranged gd by tho the association the following were appolit appointed id a comal commit ate tco 0 to td confer with the association to aseer ascertain tilli whether their arrangements were suited to successful in microscopic entertainment 0 W banks jacob Z davi i A H breckenfeld air mr Brecken breckenfeld fela addressed fh he society illustrating hia his statements with well executed watercolor water color drawings of the objects describe das wen well as with actual specimens under the microscope 4 he alluded first 0 ho first description of the alga by the tile celebrated french botanist about years ears ago 0 lie ile called the plant etla but do Can dolle e a pupil upil of rau proposed the name for the genus entis of 1805 and his su sug g been adopted by int later r botanists this plant lias has been studied by unger hassall and mr me breckenfeld showed a growing plant of Iati cheria td in a saucer of water tho plant grows in in densely interwoven tufts these be I 1 ing of a vivid green color while the thc plant is in fil tho tile actively vegetative condition changing 0 to o n u duller tint na as it ad advance to ma maturity t urt the freshwater fresh water form forin are usually usually found in ditches and runn running wg streams fet tt reams sir mr breckenfeld said ho lie had found it at nearly all times of the year i ear in iho the stretch of boggy ground inthe in the presidio olig bordering 0 the tile road to fort point tile filaments attain a length of beve several rl inches when fully developed and are of an average of or one oneto to hundred hund red and f fiftieth ol 01 nn an inch they branch but sparingly or not at all and areL characterized by consisting afu single long tube or cell not di bided by septa as is the case with tho the majority of filamentous nig re these tubular filaments are composed posed ofa of a nearly transparent cel I 1 alose wall enc enclosing losin an inner inner layer ayer thickly studded bright green grant granules ties of chlorophyll this illner layer is ordinarily pot noticeable but j t retracts from ilia lie outer envelope enve lopo when fabj subjected acted to the ac ion tion of certain reagent reagen tey or when immersed in a fluid differing in iti density from water and it then becomes distinctly visible c I 1 I 1 the plant growa grows rapidly ands and is en dowed with much vitality for it resists changes of temperature to u remarkable degree a air affords ards a choice hunting ng ground to tho the for its ta tangled massed masses arc arb the home of numberless r lessa ined soria rotifers roti fers firs and themore the more minute mi 1 bitite crus while the filaments moro more advanced in arc are are usually thickly enciu encrusted sted with diatoms here too is is i a favorite haunt of the efful zoophyte hydra codis and whose delic delicate may be bb seen grace gracefully fulli waving in nearly ever every gathering after the tile plant has attained a certain stage in its be attentively watched a marked change will be observed ll 11 near ir the ends of the filaments filament tho tile chloro phyll appears to assume a berker hue and the granules become more densely crowded this appearance increased until the extremity of the 1 tuba 6 e appears pc ars almost swollen sw ollen soon ti the de sk ly congregated granules at the tx extreme trellio end will be seen td separate from the of ot the filament a clear spore times but not always maiki tig the point of division alere heiob p seijuro or membrane appears thus I 1 binting beell a cell choc I 1 len length lenth th i ii i eliout three or four times its effin width and chos walls wall completely the clark preen mass of crowded granules these cou content tentA gradually form themi themselves elves into a spore or as it is is calleo callad to tu distinguish it from the sexual spores which are pre called ob chores bores at the extreme end of the filament which is ob conical in Bila shape pethe tho chloro phyll grains retract from tho the old cellulose wall leaving 1 a very evident evi clear space in a less notice notice able 0 degree degre this is also the tile case ir it the oilier odier parts p a arts ot the circumference of the cell and apparently tile ali 9 granular contents have secreted a sq separate rate envelope 1 entirely distinct I 1 ia 1 1 11 1 i A tua r i i 1 TM ah i U i from that of the parent farent filament the grand climax is 13 now approaching 1 9 T the fie con content of tho the cell it near car I 1 its ts base are now so dens densely b c clustered I 1 as t ere d as s to appear nl nearly arly we X while the upper half is of a much lighter hue and tho the separate grounds arc there asil easily distinguished and if very closely hatched led show an almost licille imperceptible motion theol the old I 1 fell cell wall shows signs sigus of great tension its conical extremity rounding rou rouil ding out under the slowly increasing pressure from within suddenly it gives way vi ay at the apex at the tile same instant t the now fu fully ll 11 formed acquires a rotary motion at first slow but gradually in creasing until it has gained considerable velocity its upper portion is 8 slowly twi twisted sted through the opening in in fhe apex odthe of the parent wall the rapid rotation continuing during the process of emerging it then darts aarts off with great speedy revolving on oil its major axis as Is it docs floes so when I 1 it meets an in obstacle it partially flattens itself against it then turns aside and spins off on in a new direction the motile force is is imparted to the goni dizon by dense lows ros of saving cilia with which it is is completely surrounded when it comes to rest these cilia disappear it perfectly globular in ili and after a few hours it germinates by throwing out from one to three tuf tubular iulAr prolongations which become precisely like the parent filament the method of reproduction which mr breckenfeld described as outlined above Is is entirely nonsexual being beilig simply a vegetative process 4 analogous to the budding of higher plants and tho the fission of some sonie 0 of f the lower plante and ancl alli am finals iia described also the pro pry of sexual spore 4 or yo by which the reproduction js is car can ried over ovee the winter to burst into life in the spring mr regretted that he had not descriptive powers equal to conveying cony eying an all a adequate idea 0 of f the intensely absorbing interest by thia this wonderful of spore formation he ile said he hd never would forget the bright morning when he lie witnessed witHe cd for the fint time tile entire process under tile micro microscope opa and for over over four hours scarcely moved his eye from the tube to the thoughtful thought tul observer yer ire h e doubled doubted ifancy if any in the whole range of mic microscope e would exceed this phenomenon in ill point pf af startling interest no wonder that its first observer published his re searches under the caption rap tion tho the pla plant at the moment of becoming au animal 4 in ill colial conclusion mr breckenfeld spoke eloquently of the th 3 manner wanner in bieh tile mier scope elevates humble things to places of hebr ho he said the tile stu study dy of Vau Jau chena cheria domon demonstrates mon strates how our favorite instrument phenomena of most absorbing interest in directions where the unaided eye eyo finds but little promise in will walking klug along the b banks inks of the tile little s stream tream w lacre half cone concealed caled by more pretentious t tent ious plants our humble cauch eia elia grows the average passer by if he lie notices it at all sees but a tan 91 glad d tuft of dark lark green scum yet 11 when 1 1 en this thin ia 1 examined under lie the i coic a crystal cylinder closely act et ith sparkling emeralds is is revealed and ul although though so transparent so apparently in ill structure oi ke that not seem pr fur even the finest details s k our search y yet et almost as wo daiell it n eslic changed appear wo the bright bright g 9 green green granules impelled by an tin unseen force s apar ate and rearrange themselves them in in new formations e du out t fro from parent filament the strange power we c call lif doubly mysterious when manifested in iii an organism so ro simple as thia ho 60 open to our burch bearch beems to challenge us to discover its ita secret and armed with our glittering lenses and our flashing E elands ands of workmanship ork ad hip we search i intently but in in vain ta in AD and yet et not in fil vain for we are more t than tan becom cited cd by tho the wondrous won dious revelations echela beheld and the unalloyed pleasures ples enjoyed i through the study of even tho the u unpretentious |