582 GLOSSARY 



stratum (stra' turn). One of a series of layers; stratified (straf I fid), arranged in 



layers. In ecology, stratification refers to vertical distribution at a particular 



location, 

 striated (stri' at 6d). As applied to muscle fibers, cross-banded. 

 strobila (strobi'la). A chain of individuals produced by budding from the scy- 



phistoma of a scyphozoan; also now being applied to a tapeworm colony. 

 sub- (siib). L. ; under, below. 

 succession (sQk sfsh' tin). The successive occupation of a given area by different 



types of animals; adj., successional. 

 super- (sii' per). L. ; over, above. 

 superficial (su per fish' al) cleavage. Cleavage which results in a layer of blastomeres 



surrounding a central mass of yolk. 

 supra- (su' pra). L. ; over, above. 

 suture (su' tyiir). A line of junction. 



Swanunerdam (swam' er dSm), Jan. Dutch zoologist; 1637-1680. 

 Sylvius (sir vl lis). Jacobus. French anatomist; 1478-1555. 

 symbiosis (sIm bl 5' sis). An intimate association of two organisms of different 



species, neither of which can flourish in the absence of the other; adj., symbiotic 



(sIm bl of Ik). 

 symbols. Selected symbols in common use in zoology are: 



cf signifies male. 

 9 signifies female. 

 9 signifies neuter. 



n signifies micron (J'looo millimeter). 

 Hfi signifies millimicron (Hooo micron). 

 X signifies crossed with; also magnified by. 

 = signifies a synonym. 



? signifies doubt. 



! signifies aflarmation. 



symmetry (sIm' me tri). Regularity of form, or balance between parts; adj., sym- 

 metrical (si met' rl kal). 



syn- (sin). G.; together (syn- becomes sym- before b, m, and p and syl- before 1). 



synapse (si nSps'). The area of contact of two nerve fibers from different neurons. 



synapsis (si nftp' sis). The union of two similar chromosomes, one from each parent, 

 in the growth period of gametogenesis; adj., synaptic. 



syncitium (sin sish' I um). A mass of protoplasm containing many nuclei but not 

 divided into separate cells; adj., syncytial. 



syngamy (sin' ga ml). The union of two sex cells to form a zygote. 



system (sis' t6m), anatomical. An association of organs for the performance of some 

 general activity of the body. 



systemic (sis t6m' Ik). Applying to the body generally. 



Tact (takt). L.; touch; tactile (tak' tU), pertaining to touch. 



tarsus (tar' sGs). The ankle bones in vertebrates; the distal segments of the legs in 



insects and spiders; adj., tarsal, 

 taste bud. A group of gustatory cells with supporting cells forming an organ of 



taste, 

 tax (taks). G.; an arranging, or arrangement. 



tegumentary (tgg u m6n' ta rl). Pertaining to the skin, or integument. 

 tele (tel'e). G.; far, far off. 

 telencephalon (t6l 6n s6f' al6n). The most anterior region of the vertebrate brain, 



including the cerebral hemispheres and olfactory lobes. 



