28 GENERAL BIOLOGY 



lo. Well or ill-adapted for visiting and pollinating this 

 flower. 



4. The relative fitness of the different flowers visited by one 

 kind of insect to profit by its visitation. 



A more careful study should now be made of the relations 

 existing between one kind of insect and the many kinds of 

 flowers it visits. This is a study of the relative fitness of 

 the several flowers to avail themselves of its services as an 

 agent of pollen distribution. Clearly fitness in this case 

 consists in i) oft'ering the insect an accessible food supply 

 to win its visits, and 2) having anther and stigma located 

 aright for proper pollen transference. 



Study 4. All the fiowers visited by some common insect. 



Apparatus needed and general directions, as for preceding 

 study. An insect should be selected that is abundant, that 

 is an active flower visitor; it should have a rather long 

 proboscis in order that it may have access to flowers of con- 

 siderable variety. It should be carefully examined, before 

 the proper work of this outline is undertaken, as to i) its nec- 

 tar-gathering parts, particularly as to the length and posi- 

 tion of its proboscis; 2) the position and structure of its 

 pollen brushes; and 3) its size and weight, and 4) the position 

 of its appendages when at rest. 



The record of observations. — In the field one should ex- 

 amine freshly blooming clumps of as many kinds of flowers 

 as possible, first seeing whether the insect selected for study 

 is visiting them, and if so, watching it carefully and quietly 

 until the points given below as table headings have been 

 determined : 



1. Name of flower. 



2. Furnishes pollen or nectar. 



