264 LAB El- IXC AXD STORIXu PREPARATIOXS [O/. IX 



The author has found stiff cards, 12 l .x7 '• cm., like those used for catalog- 

 ing books in public libraries, the most desirable form of catalog. A specimen 

 that is for any cause discarded has its catalog" card destroyed or stored apart 

 from the regular catalog. New cards may then be added in alphabetical order 

 as the preparations are made. In fact a catalog on cards has all the flexibility 

 and advantage of the slip system of notes (See Wilder & Gage. p. 45). 



Some workers prefer a book catalog. Very excellent book catalogs have 

 been devised by Ailing and by Ward ( Jour. Roy. Jlicr. Soc, 1S87, pp. 173, 

 34S; Amer. Monthly Micr. Jour., iScio, p. 91; Amer. Micr. Soc. Proc, 1SS7, p. 



The fourth division has been added as there is coming to be a strong belief, 

 practically amounting to a certainty, that there is a different structural appear- 

 ance in many if not all of the tissue elements depending upon the age of the 

 animal, upon its condition of rest or fatigue; and for the cells of the digestive 

 organs, whether the animal is fasting or full fed. Indeed as /•hysiofvgiut/ his- 

 iolagy is recognized as the only true histology, there will be an effort to deter- 

 mine exact data concerning the animal from which the tissues are derived. 

 (See Minot, Proc. Amer. Assoc. Adv. Science, 1S90, pp. 271-289; Hodge, on 

 nerve cells in rest and fatigue, Jour. Morph., vol VII. ( 1892 ), pp. 95-16$; lour. 

 Physiol., vol. XVII., pp. 129-134; Gage, The processes of life revealed by the 

 microscope; a plea for physiological histology, Proc. Amer. Micr. Soc, vol. 

 XVII. 11S95), pp 3-29; Science, vol. II., Aug. 23. 1893, pp. 209-21S. Smith- 

 sonian Institution; Report for 1S06, pp. 381-396. 



CABINET FOR MICROSCOPIC PREPARATIONS 



; 370. While it is desirable that microscopic preparations should be 

 properly labeled and cataloged, it is equally important that they should be pro- 

 tected from injury. During the last few years several forms of cabinets or 

 slide holders have been devised. Some are very cheap and convenient where 

 one has but a few slides. For a laboratory or for a private collection where 

 the slides are numerous the following characters seem to the writer essential : 



(i). The cabinet should allow the slides to lie flat, and exclude dust and 

 light. 



(2). Each slide or pair of slides should be in a separate compartment. 

 At each end of the compartment should be a groove or bevel, so that upon 

 depressing either end of the slide the other may be easily grasped (Fig. 210). 

 It is also desirable to have the floor of the compartment grooved so that the 

 slide rests only on two edges, thus preventing soiling the slide opposite the 

 object. 



(3h Each compartment or each space sufficient to contain one slide of 

 the standard size should be numbered, preferably at each end. If the com- 

 partments are made of sufficient width to receive two slides, then the double 

 slides so frequently used in mounting serial sections may be put into the cabi- 

 net in any place desired. 



(4). The drawers of the cabinet should be entirely independent, so that 



