1G 1>I LTOMAOB i . 



name of vessel, date, and collector's name, should be noted on 

 the label. 



Recent gatherings of DicUomaeece, These are the most valu- 

 able, important, and rich of the gatherings containing diatom- 

 ou which the student depends for material for investiga- 

 tion, and they are so various in character that it becomes dif- 

 ficult to give general directions that will serve to indicate the 

 modes of procedure to be followed in securing them. To col- 

 lect diatoruacea? at all thoroughly, a considerable amount of 

 knowledge of their habits is necessary. In general, it may be 

 said that gatherings should be made of marine plants, or alga*, 

 as they are called, which grow entirely submerged beneath the 

 water, attached to rocks, piers, iron or wood-work. The dirtier 

 such plants appear to the naked eye, the richer will be the har- 

 vest of minute organisms secured, as the brown coating, seen 

 upon aquatic plants and. similar submerged objects, obscuring 

 them, is but a mass of living diatomacea?. The larger and 

 coarser alga?, — more especially those having a slimy feel, — do 

 not usually yield many diatomacea?; but the finer brown, red, 

 or green filamentous kinds are commonly covered with them. 

 Detached fragments thrown up upon the beach ought not to be 

 kept if living ones can be found, for they usually have had the 

 diatoms rubbed off from them, and are, besides contaminated 

 with sand. The living alga? taken from their attachment should 

 be dried without washing or much compressing, and may then 

 be placed in layers, each specimen being plainly labeled with 

 the exact locality, date of collection, and collector's name. 

 Fragments of alga?e, which may break off from cabinet speci- 

 mens, and would be rejected by students of the algo?, may yet 

 be of value to the diatomist. Some of the finest collections I 

 have ever seen were derived from this source. When known, 

 the name of the alga should be stated. If possible, it is ex- 

 tremely desirable to secure specimens of diatom-encrusted alga? 

 in spirits. In this way the diatoms will be preserved in almost 

 their natural condition; and those species which are filament- 

 ous or grow in chains, will be available in that condition for 

 study. 



Fresh water plants clouded with diatomacea? may be collected 

 and preserved in the same manner as marine alga?. As has 



