31 



. 

 tribution map and giving all the accession numbers and where the 

 specimens are to "be found in the collection, and after it all the notes 

 on that species. 



In keeping these records the office clerk enters any data stamped on 

 the letter in the correspondence file and the food catalogue. He also 

 makes all entries of the food catalogue and accession catalogue on the 

 distribution map card, which gives the position of the specimen in the 

 collection. 



Two collections are being formed, one an ordinary systematic col- 

 lection and the other an economic or biologic collection, arranged 

 according to the food plants of the insects and the parts of the plant 

 attacked. Both collections are kept on the Cornell block system, in 

 glass cases, with the exception that cork carpet is used instead of the 

 larger sizes of blocks, which are prone to warp. Where the insects 

 are placed in the collection according to the food plant, it is mani- 

 festly impossible to find a specimen which may have a number of food 

 plants, or if one does not happen to remember the food. To obviate 

 this a system has been devised whereby the accession number indi- 

 cates the place of the specimen in the collection. If the specimen is in 

 the systematic collection, an "S" is placed after the number, as 321 S, 

 and is at once easily found in its proper place. For indicating the 

 place in the economic collection a fractional number is used in which 

 the numerator is the accession serial number, and the denominator 

 indicates its position in the collection the same as a shelf number in 

 a library. Indeed, the same system is used. Each block is numbered 

 the same as a book, according to the decimal system. For this I have 

 used a modification of the outline furnished by the library of the 

 United States Department of Agriculture for the classification of the 

 books on agriculture. This brings all plants of a natural group under 

 a given number and gives each individual plant a number indicating- 

 its position in the larger group. Also the part of the plant attacked 

 is indicated by a number following a dash after the plant number. 



Thus op 9 p would mean that the specimen is a larva (L), accession 



No. 176, and is to be found at 36.26 in the collection. 



This later number is to be found on the front of the case in which 

 the specimen is, or is included in the numbers of the first and last 

 specimens in that case which are given on the front. The first digit 

 of this number (3) indicates that the plant is a vegetable-garden vege- 

 table; the second (6) that it is a solanaceous plant; the first digit 

 after the decimal point that it is the tomato, whose number is 36.2. 

 After this the 6 indicates that it is the fruit of the tomato which is 

 injured. In like manner had this accession number a denominator 

 11.66 it would indicate that the insect affects the fruit (ear) of corn 

 and is to be found at that point in the collection, or 15.16, cotton, etc. 

 This number can be readily found by referring to the general decimal 



