FIELD I 

 Columns 3 5 and 36 



4G Myelin sheath (= medullary sheath) 



4H Neurilemma (= sheath of Schwann) 



5 Supportive tissue, unspecified 



51 Cartilage, unspecified 



52 Hyaline cartilage 



53 Elastic cartilage 



54 Fibrous cartilage 



55 Bone tissue, unspecified 



56 Intramembranous bone tissue (to be used when a test compound affects this bone tissue type 



differently than it affects intracartilaginous bone) 



57 Intracartilaginous bone tissue (to be used when a test compound affects this bone tissue type 



differently than it affects intramembranous bone) 



58 Dentine of teeth 



59 Enamel of teeth 

 27 Pulp of teeth 



6 Body fluid, unspecified; plant fluid, unspecified 



61 Extracellular fluid (= intercellular fluid; intercellular lymph); tissue juice. 



(Lymph: This liquid tissue, contained in lymphatic vessels, is not coded in Field I, but 



always in Field H as an organ. See Field H, symbol series 35-. ) 

 (Blood: This liquid tissue and its components [plasma and cells], contained in circulatory 



vessels, are not coded in Field I, but always in Field H as an organ and its parts. See 



Field H, symbol series 33-. ) 



62 Synovial fluid (= synovia) 



63 Cerebrospinal fluid (to be used when the cerebrospinal fluid of a particular part of the central 



nervous system [coded in Field H-l] is affected. When the cerebrospinal fluid, as a whole, 

 is affected, it is coded in Field H- 1 [Symbol 1 55]. ) 



64 Secretion (product of a gland) (to be used only when a test compound affects the composition 



of a gland's secretion. When only the volume of secretion is affected, the effect is adequately 

 coded by indicating increase or decrease of secretion in Field T and the gland affected in 

 Field H-l. ) 



65 Thyroid gland colloid substance 



7 Plant tissues, in toto 



71 Meristem 



72 Sclerenchyma 



73 Cortex; cortical parenchyma; collenchyma; cortical sclerenchyma 



74 Epidermis; cuticle (--in leaves, unspecified as to whether it is upper or lower epidermis or 



cuticle or both upper and lower). (For upper or lower epidermis specifically, use Symbols 7R 

 or 7S.) 



75 "Bark". (This term is defined to include all tissues outside the cambium layer. ) 



76 Pith; pith parenchyma 



77 Endodermis 



78 Cambium; vascular cambium. (For cork cambium, use Symbol 7E. ) 



79 Pericycle 



7A Xylem. (For specific xylem elements, use Symbols 7F, 7G, 71, 7M, and 7N. ) 



7B Phloem. (For specific phloem elements, use Symbols 7J, 7K, 7L, 70, and 7P. ) 



7C Mesophyll of leaves 



7D Cork 



7E Cork cambium 



7F Xylem vessel 



7G Xylem tracheid 



7H Resin duct; latex vessel (= lactiferous duct) 



71 Wood parenchyma; xylem parenchyma 



7J Phloem sieve tube 



7K Phloem companion cell 



7L Phloem parenchyma cell 



7M Primary xylem 



7N Secondary xylem 



70 Primary phloem 



7? Secondary phloem 



7Q Vascular bundle, in toto 



7R Upper epidermis of leaf 



- 112 



