404 BULLETIN OF THE BUREAU OF FISHERIES. 



by hand can be thoroughly searched in a relatively short time, while those which are at 

 greater depths require repeated collections extending through several years before we 

 can be reasonably sure of having a fair representation of the species growing there. 

 Collins has aptly compared the collections of algae obtained by dredging with those of 

 other plants which might be gathered from a large field on a dark night by means of an 

 aeroplane and a long rake. In clear, still water the use of a glass-bottom boat or bucket, 

 enabling one to see the algae which are growing at considerable depths, may be used to 

 advantage, but in this region one can not see farther below the surface with a glass- 

 bottom boat than without it. 



The large, coarse algae, which are more abundant farther north and are represented 

 here only by Fucus, need no special care after being collected, but most other algse are 

 easily injured. These may be carried for a short time in an ordinary collecting can or 

 other vessel that will protect them from the sun and keep them moist, but they should 

 be placed in sea water as soon as possible, preferably as soon as they are collected. In 

 any case, a large-mouthed bottle should be carried to hold the smaller, more delicate 

 species that may be found. 



Farther north, where the air temperature is much higher than that of the water, 

 most algae die soon after being gathered, since they can not endure the change of tempera- 

 ture to which they are exposed; but in this region algae may be kept for days in jars of 

 sea water, provided that they are clean and that very few specimens are placed in each jar. 



For preservation, the algae should be dried. Large, coarse species, as Fucus, may 

 be dried between blotters under pressure or may even be spread out and allowed to dry 

 in the air. In the latter case, however, it is difficult to make them lie flat when it is 

 desired to mount them on paper. All other forms should be mounted on paper as soon 

 as possible, any thick, unglazed paper being suitable for this. With the larger, more 

 rigid, specimens, one may simply shake off the water and spread these out on the paper. 

 The more delicate specimens should be floated in sea water, the paper slipped under them, 

 and the algae arranged on the paper, needles being used if necessary. The hand is then 

 placed under the center of the paper, and this, bearing the specimen, is carefully removed 

 from the water. The alga is then arranged on the paper in the position that shows it to 

 greatest advantage, needles and water dropped carefully upon it from a pipette being 

 most useful for this operation. 



Having mounted the specimens, one should then dry them under moderate pressure 

 between plant driers or blotters, first laying some thin, white cloth over the algse to keep 

 them from sticking to the driers. A very good plant press may be made from boards 

 weighted with stones. The driers should be changed at least twice a day and should 

 be thoroughly dry when used. Specimens should be kept in the press until all moisture 

 is removed from them. 



Microscopic forms should be mounted in such a way that they may be examined 

 with the microscope, thin sheets of mica being good for this purpose. The brittle coral- 

 lines are always difficult objects to handle. Some of them may be pressed flat while 

 living and may then be fastened to paper by gummed tape. They should be kept in 

 folders to preserve any fragments that may be broken off. Some minute algae adhering 

 closely to rocks can best be preserved by breaking off pieces of the rock on which they 

 are growing. Any specimens that do not adhere to paper may be fastened on with 

 gummed tape. 



