DESCRIPTIVE CATALOGUE OF RECENT FORAMINIFERA. 257 



with a good acromatic lens magnifying about 10 diameters, is mosl 

 convenient. A small quantity of the material in a shallow watch glass 

 blackened on the under side, being placed under the lens, is carefully 

 inspected, and when a specimen is found which it is desired to pre- 

 serve it may be readily removed by means of a very line camel's hair 

 pencil slightly moistened between the lips. Transfer of specimens 

 should be attempted with the moistened pencil only, as the use of forceps 

 is certain to crush the delicate shells. 



For preservation of the identified specimens in numbers for study 

 nothing is better than wooden slides of regulation size — 1 by 3 inches. 

 These may have either a concavity drilled in one side nearly through 

 the wood and painted black, or a hole bored entirely through the slide 

 and one side covered with heavy blackened paper. A removable cover 

 to this little cavity may be cut from a thin sheet of mica, and held in 

 place either by a spring clamp or by slipping it under the thin paper 

 front of the slide, which is left unglued about the center for that 

 purpose. 



To make a section the specimen should be attached in the desired 



attitude to the face and near the end of a glass slip by means of the 



^JLininutest drop of liquid glue. The attitude of the specimen must be 



^ carefully preserved until the glue has set. The shell is then covered 



V with chloroform or xylol balsam, which may be made to penetrate the 



^* chambers of the shell and be rapidly hardened by the application of 



«** direct heat up to the boiling temperature. Superfluous balsam being 



cut away, the shell supported by the balsam is rubbed lightly upon a 



hone, kept thoroughly wet with water, until the desired section is 



exposed. The balsam is then dissolved away by chloroform, and the 



glue by water, and the specimen mounted. 



The manner in which specimens shall be mounted will depend upon 



^* the preferences or ingenuity of the preparator, and the arrangements he 



«^ may make for the storage of his collection. If a cover-glass is used it 



")\ should not be sealed on, as the underside of the glass is almost certain 



to "sweat" sooner or later, and obscure the specimen. It may be worth 



while to say that for the attachment of the shells to any surface the 



author has not found anything better than microscopists , gold size. 



The best instrument for transferring the minute drop of adhesive 



material of whatever kind to the point where the shell is to be attached 



is the finest obtainable sewing needle, the eye end inserted in a slender 



handle and the point broken off at the thickest part of the needle. 



r^ The literature of the subject is very large, though most of it is to be 



r^ found in journals of natural history and transactions of societies. With 



^ Carpenter's "Introduction to the Study of the Foraminifera," Brady's 



\ "Ueport on the Foraminifera collected by H. M. S. Challenger," and 



J Sherborn's •• Index to the Genera and Species of the Foraminifera," the 



S» student will be able to begin work in an intelligent manner and to find 



* references to all that has been published on this subject up to the most 



5jf recent date 



V"~ NAT MUS !)7 17 



