A REVIEW OF THE PHYLA, SUBPHYLA, AND CLASSES OF 



ANIMALS 



The following study is outlined as a review of the animal 

 groups through the use of a key for their identification. The key 

 is designed to include the forms which are ordinarily used in 

 laboratory studies or which one might ordinarily encounter in 

 general studies. 



Unlabeled representatives of the major animal groups should be 

 provided in numbered jars. Specimens preserved in alcohol 

 should be dipped in water and kept moist while used for study. 

 After each specimen is identified, write upon a record sheet the 

 name of the group or groups to which the animal is judged to 

 belong. Make these records according to the number borne by 

 the specimen. 



Key for the Identification of the Larger Groups of Animals 

 A. The body of the organism comprising a single independent cell or many 

 similar and independently functioning cells associated in a colony with 

 little or no differentiation {i.e., without forming tissues); or comprising 

 masses of multinucleate protoplasm; mostly microscopic 



Phylum Protozoa 

 A A. The body of the organism comprising many cells of different kinds (i.e., 

 forming tissues). 



B. Body usually forming irregular masses without apparent symmetry 

 but the masses sometimes cylindrical, goblet shaped, or vase shaped, 

 or definitely arboroid; walls rough, bristly, and pierced by numerous 

 pores, one (or more) of which is large and conspicuous 



Phylum Porifera 

 BB. Body regular in form, walls not pierced by pores and with evidence 

 of a definite symmetry. 

 C. Anus lacking, mouth capable of opening and closing. 



D. Symmetry radial or biradial, radii not five or multiples thereof. 



E. Body without rows of ciliated swimming plates; tentacles 



with batteries of nematocysts (uneven of surface); mouth 



surrounded by bases of tentacles Phylum Ccelenterata 



F. Bod}^ vase shaped (tapering toward basal end) with hypo- 

 stome, with stalk or stem for attachment, and usually 

 colonial; or body umbrella shaped, not colonial. 

 G. Body vase shaped; or umbrella shaped with velum about 



margin of umbrella Class Uydrozoa 



GG. Body umbrella shaped without velum and with oral 



arms; margin of umbrella notched Class Sajphozon 



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