OF MICROSCOPIC OBJECTS. 55 



of a quarter of an inch, and each "stem" is covered with a 

 sheath, in shape somewhat like an elongated thimble. When ripe, 

 the sheath falls off and reveals the same shaped column, made up 

 of beautifully fine net-work, with the spores lying here and there. 

 This dries well, and is a good object for the middle powers. 

 Amongst the fungi the blights of wheat and of other articles of 

 food may be included. Many of them may be mounted " dry ;" 

 others, however, cannot be well preserved except in liquids, and 

 will be referred to in Chapter IV. Amongst the zoophytes and 

 sea-mats, commonly called " sea-weeds," may be found many very 

 interesting objects to be mounted " dry." When this mode of 

 preservation is used, it is necessary that all the searsalt be 

 thoroughly washed from them. As they are, however, most fre- 

 quently mounted in balsam or liquid, they will be more fully 

 noticed in other places. 



The scales of fishes are generally mounted " dry " when used as 

 ordinary objects ; but for polarized light, balsam or liquid must 

 be used, as noticed in Chapter III. The variety and beauty of 

 these are quite surprising to the novice. It is also very interest- 

 ing to procure the skin of the fish when possible, and mount it 

 on a separate slide to show how the scales are arranged. The 

 sole is one of the most unusual forms, the projecting end of each 

 scale being covered with spines, which radiate from a common 

 centre, while those at the extremity are carried out somewhat 

 resembling the rays of a star. One of the skates has a spine pro- 

 jecting from the centre of each scale, which is a very curious 

 opaque object, especially when the skin is mounted in the manner 

 described. The perch, roach, minnow, and others of the common 

 fishes give the student good objects for his cabinet, and may be 

 procured without difficulty. 



Insects which are very transparent, or have the " metallic lustre" 

 with which any medium would interfere, are mounted " dry." 

 The diamond-beetle, before mentioned, is a splendid example of 

 this ; the back is generally used, but the legs, showing the curious 

 feet, are very interesting objects. Indeed, amongst the legs and 

 feet of insects there is a wide field of interest. When they are 

 of a " horny " nature, it is best to dry them in any form prefer- 

 red, but to use no pressure ; when, however, they are wanted flat, 



