GENERAL BIOLOGY 



III. INTERRELATIONS BETWEEN DIFFERENT SPECIES. 



If the species which you are studying is always associated with 

 some other species, in which of the following groups does it belong? 



1. Commensalism. The commensal alone benefits, but the host 

 is not injured. In the case in hand, which is the commensal and 

 which the host? Is the commensal permanently fixed to the host, 

 or free to separate on occasions? 



2. Symbiosis. The symbionts derive mutual benefit from asso- 

 ciation. These also may be free or fixed. 



3. Parasitism. The parasite benefits at the expense of the host. 

 Is the parasite an endoparasite or an ectoparasite? Is it temporary 

 or constant? 



IV. COOPERATION BETWEEN INDIVIDUALS OF THE SAME SPECIES. 



Associations of individuals of the same species fall under one 

 or another of the following heads : 



a. Colonial forms without division of labor. 



b. Colonial forms with division of labor. 



c. Association of separate individuals without division of labor. 



d. Association of separate individuals with division of labor. 



1. Does the form which you are studying belong in any of 

 these groups ? What advantage, if any, is derived from association 

 without division of labor? If physiological division of labor is 

 present is it associated with structural diversity? If so, draw each 

 of the types present, and determine their relations to one another. 



2. Study a colony of bees, or of ants, and draw figures of the 

 males, females and workers. Observe the varied activities of the 

 members of the colony. If other members (castes, slaves) are 

 present in the ant colony make a study of them also. Note the way 

 in which the food is stored and the young are cared for. Study 

 a section through honey comb, and if possible, observe the method 

 in which it is formed. Observe and draw to scale worker cells, 

 drone cells and queen cells, and if possible observe the kinds and 

 relative quantities of food which are fed to the larval workers and 

 queens. 



V. SEXUAL REPRODUCTION. 



i. Sex. In many plants and lower animals the sexes are united 

 in the same individual (Hermaphroditism) ; in higher animals the 

 sexes are generally separate (Gonochorism). To which class does 

 your specimen belong? 



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