Journal of Applied Microscopy. 



181 



2. When the reference mark upon 

 which the cross-wires are to be set is of 

 about the same order of magnitude as 

 the movable wire, the method of super- 

 posing one upon the other (B) gives the 

 best results. 



• 3. When the refei'ence mark is larger, 

 such, for example, as the lines on a 

 giaduated scale, methods C or D should 

 be used. The choice between these 

 methods depends upon the observer; if 

 he has keen eyesight, he should set the 

 parallel wires near the edges of the ob- 

 ject observed (C); but for those who 

 have the ability to make correct esti- 

 mates of distances, method D will be 

 found satisfactory. 



James S. Stevkns. 



University of Maine. 



American Postal Microscopical 

 Club. 



This club, after the usual summer va- 

 cation, is now entering upon its twenty- 

 fourth year of successful operation. As 

 is well known to the older class of 

 microscopists, it holds no regular meet- 

 ings, being wholly a correspondence so- 

 ciety that circulates slides through the 

 mails, and comments on the same, in or- 

 der to interest the members in each 

 other's work and ideas. Prom twelve to 

 fifteen boxes of slides usually pass each 

 member during the club season, from 

 October to June. Besides postage on the 

 boxes and letters, and a one dollar en- 

 trance fee, the dues are annually one 

 dollar, and one slide with descriptive 

 note. The membership is widely scat- 

 tered over the various states. It is 

 neither wholly professional nor yet prac- 

 ticable for persons wholly without ex- 

 perience or skill. It is open to those who 

 are able and willing to be really useful 

 members, whether great or small. Ex- 

 perts, who have much to teach and little 

 to learn, would naturally regard it 

 chiefly as a means of helping and en- 

 couraging their fellows. Any corres- 

 pondence as to membership should be 

 addressed to the president. 



The following announcement, just is- 

 sued to members, will give non-members 

 Sonne further idea of the methods of the 

 club; 



"As the circuits are now being revised, 

 and corrected lists for the year's use be- 

 ing printed, notice of actual or expected 

 changes of address should be forwarded 

 at once; also intended proposals for new 

 members, 



"Collecting boxes for a new series or 

 circuit boxes will be sent out, after a 

 few weeks, by the secretary; and mem- 

 bers are specially requested to have 



their slides ready, with notes fully pre- 

 pared, in order to avoid hasty prepara- 

 tion or interruption of the circulation 

 while waiting for them. 



"There are now a few scattering va- 

 cancies in the circuits, which it is desir- 

 able to have filled by the right persons 

 at the present time: also one entire cir- 

 cuit that could be spared for a local sec- 

 tion, but only on condition that some 

 old member, familiar with the necessi- 

 ties of the club and with the proposed 

 new members, would undertake the or- 

 ganization and supervision of the circuit, 

 and be personally responsible for keeping 

 it in good order. Members recommend- 

 ing candidates for membership should taa 

 careful to do so only on definite knowl- 

 edge, and with the understanding that 

 unquestioned ability to be a useful mem- 

 ber is not more important than the as- 

 surance of being a safe one, having 

 knowledge of the character of the work, 

 a positive and permanent interest in the 

 project, and both desire and opportunity 

 to attend personally and promptly to the 

 little duties involved." 



R. H. Waijd, M. D., President. 

 Troy, N. Y. 



A Permanent Stain for Starch. 



A very good and durable stain for 

 starch may be obtained by the use of 

 anilin-safranin and gentian-violet. 



1. Anilin-safranin: alcoholic fifty per 

 cent, solution, prepared by combining 

 equal parts of anilin water and a satur- 

 ated alcoholic ninety-five per cent, solu- 

 tion of safranin. 



2. Gentian- violet: a two per cent, 

 aqueous solution. Stain from two to 

 four hours in the safranin and from two 

 to eight minutes in the gentian violet. 

 The slides should be taken through the 

 alcohols quite rapidly, or too much of the 

 stain will be washed out. 



I have tried this on several kinds of 

 starch, always with good results. Some 

 slides with sections of the corms of 

 Erythronium, which were stained over 

 two years ago, are still of the same color 

 and intensity as they were the day they 

 were mounted. The stain is a clear 

 purplish red and makes a gooJ object for 

 demonstration purposes. Paraffin sec- 

 tions of the young corms of Erythronium 

 are especially favorable objects for show- 

 ing the position of starch in cells, and 

 by using the above method of staining 

 the cells will look perfectly clear filled 

 with the colored starch grains. 



.John H. Schaffneu. 



Botanical Laboratory, Ohio State Uni- 

 versity, Columbus, Ohio. 



