Hillman, William S. <br/><br/>
Photoperiodism in plants and animals 
William S. Hillman. 
 - Burlington, N. C.  Scientific Publications Division, Carolina Biological Supply Co.  c1979. 
 - 16 p.  ill.  25 cm. 
 - Carolina biology readers .
<br/><br/> Cover title. 
<br/><br/>Bibliography: p. 16. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Photoperiodism<br/>Plant photoperiodism.<br/>Light--Physiological effect.