72 JOURNAL OF THE [October, 



it is well to add more drops to the watch-glass, until the alga is 

 well permeated by the fluid and appears natural ; it is then trans- 

 ferred to the slide with a drop or two of chloroform, arranged 

 for exhibition, and then the balsam dropped on immediately be- 

 fore the fluid has evaporated, and then the cover may be applied. 



" Prepared in this manner, the balsam follows the chloroform, 

 and penetrates the cells of the sea-weed, making them translu- 

 cent, and showing the details of their structure admirably, while 

 the diatoms are displayed conspicuously in their natural connec- 

 tion. The balsam must be hardened slowly, as it will not do to 

 apply heat of a temperature that will shrivel the alga. Of course 

 every algologist knows that in this mode but seldom can the 

 specific marks of a diatom be made out ; but the not less im- 

 portant facts of the mode of growth, can be shown, as they can- 

 not be with cleaned diatoms. 



" I have now before me a slide holding a Ptilota from the 

 Pacific, which displays finely several species of diatoms that I 

 have seen no trace of until this method was tried. I can heartily 

 recommend it to those who have collections of algae." — Charles 

 Stodder. 



" N. B. — Instead of putting the specimen in a drop of chloro- 

 form in a watch-glass, where it evaporates in a few minutes, 

 when it is convenient it may be better to put several specimens 

 in a very small bottle of the menstruum, and take them out as 

 wanted, transferring direct to the slide, or to the watch-glass, 

 as preferred. In this way they may be well saturated with 

 chloroform. The next important matter is to add the balsam 

 before the chloroform has all evaporated." — C. S. in The American 

 Journal of Microscopy, Vol. II. (1877), p. 142. 



Mounting Alg.e. — " The article by Mr. Charles Stodder in 

 your last number on ' Mounting Diatoms in Situ,' was not with- 

 out considerable interest to me, and no doubt to others who 

 have tried their hands at mounting marine algge in a way to 

 show their best points. I believe that workers in microscopy 

 should do as good camp-meeting attendants do — everyone should 

 get up and relate his or her experience. Now as I have done 

 considerable lately in the way of mounting marine algse, I think 

 it my duty to advocate the use of the material that has given me 

 the most satisfactory results, /. e. salicylic acid. My process is 



