FIELD T-3 

 Columns 62, 63, and 64 



271 Co-carcinogenic: a compound that possesses no carcinogenicity of its own, but causes an 



increase in the carcinogenic action of another agent. Use Symbol 271 only with Symbol 8 

 coded in Field T- 1 with Symbol 43 or 47 coded in Field T-2 (or, if a virus is the cause of 

 the neoplasm. Symbol 1 coded in Field T- 1 with Symbol 43 or 47 coded in Field T-2). 



272 Carcinostatic: a compound that temporarily or permanently slows or halts the growth of a 



tumor, but does not cause its regression. Use Symbol 272 when Symbol 44, 46, or 47 of 

 Field T-2 is coded with Symbol 2 of Field T-1; also, when Symbol 44 or 46 of Field T-2 

 is coded with Symbol 3 of Field T-1; and wtien Symbol 43 or 47 of Field T-2 is coded with 

 Symbol 9 of Field T-1. Do not use Symbol 272 for compounds that cause a tumor to regress. 



273 Carcinoclastic: a compound that produces a lasting destructive effect on a tumor as judged 



by regression (degeneration) attributable to the action of the test compound. Use Symbol 

 273 only when Field T-2 is coded with Symbol 45 and Field T-1 is coded with Symbol 1 or 7 

 (or when Field T-2 is coded with symbols of the 418- series and this degeneration coded 

 in Field T-2 refers to the tumor coded in Field E). 



Series 3-- 



Categories of agents candidate for practical use in affecting growth and 

 development and physiological processes of plants . (For control of plant 

 populations, see symbols of series 1--, Symbols 104, 107, and 108.) 



301 Plant growth-affecting agent; stimulant or depressant of plant growth. Use Symbol 301 in 



Field T-3 when any of the following specific processes or qualities (Field T-2) are increased 

 or decreased above or below the normal (Symbol 1 or 2 of Field T-1): 



Field T-2 symbols, inclusive 



Infection; infestation 18-181 



Crop yield 19-194 



Cell division 21 - 212 



Cell growth 22-227 



Spore germination 25 - 252 



Seed germination 26 - 262 



Growth of plant organ 28 - 2831 



Growth of the entire plant 2A - 2A42 



Also use Symbol 301 for growth-influencing agents which are essential for (Symbol 7 of 

 Field T-1) or decrease or prevent (Symbol 2 or 3 of Field T-1) any of the following specific 

 processes or qualities (Field T-2): 



Cell differentiation 23-2315 



Tissue differentiation 27 - 272 



Organ formation 284 



Abnormal tissue or organ formation, 



except tumors 412 - 4151 



Neoplasia or incidence of tumors 43, 44, 47 



302 Maturation agent. Use Symbol 302 for agents which promote, decrease, or prevent (Symbol 1, 



2, or 3 of Field T-1) any of the following specific processes of Field T-2. (For agents 

 affecting flower formation or formation of any other specific organ's development and 

 maturation, use Symbol 301; for agents affecting reproductive maturation of the organism, 

 use Symbol 305. ) 



Field T-2 symbols, inclusive 



Ripening, maturing process 2B 



Aging symptoms 2C 



Normal pigmentation and coloring as 



indication of maturation F824 and FA24 



- 171 



