234 STUDY OF COMMON PLANTS. 



RELATIONSHIP. 



Compare with this species as many others of the same 

 family as can be obtained. Note especially 



I. Any general external charactei's in which they agree. 



II. The inflorescence, which in this family presents very 

 interesting peculiarities. 



III. The structure of the flowers, differing in details in 

 the different genera, but showing marked agreement in 

 plan. 



IV. The characteristic fruit. 



V. Structure and position of the seeds. 



Write a brief summary of the features that you consider 

 characteristic of the family. 



The Borraginacese include about twelve hundred species, 

 widely distributed throughout the world. A number of 

 ornamental ones are common in cultivation. Some have 

 been employed in medicine, and the curious doctrine of 

 signatures is still called to mind by such names as lung- 

 wort and stonewort. The marked variety of external 

 appearance, in connection with great persistence of essen- 

 tial characters, as seen, for example, by comparison of the 

 exquisitely beautiful and fragrant heliotrope with the 

 coarse and rank hound's-tongue, is interesting as suggest- 

 ing how widely the different genera have diverged in 

 externals from earlier forms, while still retaining their 

 most deeply seated ancestral traits. 



The student will do well to make a special study of the 

 inflorescence as it presents itself in various members of 

 the family, and in the same connection review the whole 

 subject of floral arrangement as presented by G-ray,. Les- 

 sons, Sec. VIII, or Structural Botany, Chap. V. 



