386 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



increased the iiioie simple the iipi)liauces of the hiboratory. Hence, 

 during" a short stay at the seashore for the purjjose of study of these 

 forms, where the equii)ment of a hastily eoustructed laboratory is neces- 

 sarily meager, great inconvenience is experienced. 



In order to obviate this difficulty 1 have used a method Avhicli I found 

 both simi)le and satisfactory. Small bags having the shape repre- 

 sented in the accompanying figure arc made of bolting cloth, a line 

 mesh being used so that the desired organisms can 

 not pass through. The organisms having been 

 removed by means of an ordinary glass tube from 

 the glass dish in which the surface nets were 

 emptied, are now transferred to the bag just de- 

 scribed. During this manipulation the little bag 

 is kept open by jncans of a pair of forceps in the 

 manner indicated, after which the bag is securely 

 (jlosed by tying a string around its mouth. Several 

 bags filled in this way are then placed in an Erle- 

 meyer flask or, in the absence of this, into a com- 

 mon wide-mouth bottle. 



A suitable Aveight, preferably a glas's rod, having 

 been i»laced on the bags to i)revent them from 

 floating, the solution of chronue acid is now poured 

 over them and permitted to remain in contact lor 

 twenty-four hours. The bags are then removed, 

 and having been attached to a long piece of cord, 

 with an interval of 2 or 3 inches betAveen every two 

 bags, the whole is tied to any convenient object 

 and washed in a stream of water until free from 

 the chromic acid. This usually takes about two 

 hours. The bags are now removed from the Avater 

 and immersed in the staining fluid for a suflicient 

 time. The excess of stain is washed away in 

 water, and if overstaining has occurred the organ- 

 isms can be decolorized while still inclosed in the bags by adding a 

 trace of HCl to the water. The bags are now cut open, the stained 

 organisms transferred to a watch glass and mounted. Should they still 

 be overstained they can be further decolorized in the manner stated. 



