1869.] ^'^'- [Wood. 



From the time wlien the weather first grows cool in the fall, on until 

 the cold weather has fairly set in, and the reign of ice and snow com- 

 mences, is the period during which the algae hunter should search care- 

 fully all wet, dri'pping rocJcs, for specimens. Amongst the dew bearing 

 stems of wet mosses — in dark, damp crevices, and little grottoes beneath 

 shelving rocks — here, at this season, is the algae harvest to be reaped. 

 Nostocs, palmellas, conjugating desmids, sirosiphons, various unicellular 

 algae, then flourish in such localities. My experience has been, that late 

 in the fall, ravines, railroad cuttings, rocky river-banks, &c. , reward time 

 and labor better than any other localities. 



The vaucherias, which grow frequently in wet ground, as well as sub- 

 merged, fruit in the early spring and summer in this latitude, and are 

 therefore to be collected at such times, since they are only worth ijreserv- 

 ing when in fruit . 



In regard to algae which grow on trees, I have found but a single spe- 

 cies, and do not think they are at all abundant in this latitude. Farther 

 south, if one may judge by Professor Kavenel's collections, they are the 

 most abundant forms. 



As to the preservation of the algae— most of the submerged species are 

 ruined by drying. Studies of them should always, when practicable, be 

 made whilst fresh. Circumstances, however, will often prevent this, and 

 I have found that they may be preserved for a certain period, say three 

 or four months, without very much change, in a strong solution of acetate 

 of alumina. If this is not to be had, I would recommend a trial of a 

 preservative liquid, made of glycerine, carbolic acid (creasote of the 

 shops), and water. This mixture might be made by dissolving half an 

 ounce of pure carbolic acid (a little more of the impiire), in three fluid- 

 ounces of glycerine, and adding a full pint of pure water. 



Almost all species of algae which are firm and semi-cartilaginous, or 

 almost woody in consistency, are best preserved by simply drying them, 

 and keeping them in the ordinary manner for small plants . When studied, 

 fragments of them should be soaked in water. 



The only satisfactory way that algae can be finally prepared for the 

 cabinet is by mounting them whole, or in portions, according to size, for 

 the microscope. Of the best methods of doing this, this is hardly the 

 place to speak ; but a word as to the way of cleaning them will perhaps 

 not be out of place. Many of them, especially the larger filamentous one, 

 may be washed by holding them fast upon an ordinary microscope slide, 

 with a bent needle or a pair of forceps, and allowing water to flow or slop 

 over them freely, whilst they are rubbed with a stifi&sh camels hair pencil 

 or brush. In other cases, the best plan is to put a mass of the specimens 

 in a bottle half full of water, and shake the whole violently ; draw off the 

 water from the plants in some way, and repeat the process with fresh 

 additions of water, until the plants are well scoured. At first sight, this 

 process Avould seem exceedingly rough, and liable to spoil the specimens, 

 but I have never seen bad results from it, at least, when practised with 

 judgment. The water seems so to envelope and protect the little plants 

 that they are not injured. 



