LOBSTEE OE OEAYFISH 165 



h. The sub-oesopliageal ganglion. — Compare with 

 a in shape and size. 



Is there any connection between the ganglion 

 and the "brain"? 



c. The thoracic ganglia. — How many are there? 



How are they situated ? Are they connected with 

 one another ? How do they compare in shape 

 and size with a and i ? How many in each seg- 

 ment ? To what parts do their branches run ? 



d. The abdominal ganglia. — Compare in all re- 



spects with a, h, and c. 

 Make a diagram showing the shape and relation of 

 those parts of the nervous system mentioned above, 



PHTSIOLOGT 



The living animals should be studied in a pan of 

 water or in an aquarium. Though living specimens are 

 preferable, it vrill be possible to do much of the follow- 

 ing work upon the dead animal. 



a. Movements. — Can the animal walk? If so, in how 

 many different directions ? At how rapid a rate ? 

 What appendages are used for this purpose ? Do 

 all of these appendages move in the same man- 

 ner? Do all occur on the same region of the 

 body ? Can you give any reason why they 

 should be here? Do all seem to be adapted to 

 this particular function? Does the animal swim? 

 By means of what organs? "Where are these lo- 

 cated? "Why are they here? How do they 

 work ? In what direction does the animal swim ? 

 "Why in this direction? Does it use both am- 

 bulatory and swimming organs at the same time? 



