THE MICROSCOPE. 137 



tions of the different stages of development of insects can be made 

 by putting eggs, young and old larvae, pupae, and imagos in a glass 

 tube filled with spirit, and having a stopper of cotton wool, then 

 placing them, according to their age, in a stoppered upright vessel 

 filled with spirit, in the middle of which is a cylindrical glass, which 

 presses the glass tube against the side of the upright vessel. 



To make tape-worms, long nemertines, long annelids, and 

 similar organisms satisfactorily visible, he rolls them spirally on a 

 thick glass tube and then places them in an upright cylindrical 

 vessel of spirit on a little wider than the tube. The worm is fastened 

 to the top and bottom of the latter by means of a fine white-silk 

 thread, or, better still, with isinglass. 



Very instructive sections of small mammalia, birds, frogs, fishes, 

 and crustacea, can be made by attaching them to a board, dorsally, 

 ventrally, or laterally, according to the section, and imbedding them 

 in a freezing mixture, until they are quite frozen through. Then 

 cut them with a broad-bladed knife, or saw if necessary, % attach to 

 the section-plane a glass plate, and lay the preparation is strong 

 spirit until all viscera become so hardened that the}- retain their 

 place. Then the preparation can be cleaned and mounted. The 

 author's museum contains preparations mounted in this way of fishes 

 in which the spinal marrow, brain, olfactory nerve, swimming bladder, 

 etc., are very beautifully shown. In a longitudinal section of 

 Turdus merula, the form of the air-sac is distinguishable within the 

 breast-bone. — Zool. Anzeig. 



The " Microscope." — The first number of the third volume of 

 this valuable journal is at hand. Two and a half years ago, Prof. 

 Stowell entered upon its publication with considerable misgiving as 

 to its success, being in doubt as to whether the subject of micro- 

 scopy had become of sufficient interest in the west to warrant such 

 an undertaking. 



But its success has proved that his fears were unfounded; its 

 circulation has steadily increased from the beginning, until it is 

 now a paying institution. It has been enlarged from time to time, 

 and now contains forty-eight pages exclusive of the advertise- 

 ments. 



Its matter is improved — now very good indeed — always was 

 good — there is now a large number of contributors, and more 



