How To Study Living Animals


External Morphology of Earthworms
Materials.

Preserved earthworms, the larger the better herunterladen.

Observations.

1. In what respects are the dorsal and ventral surfaces alike? In what respects different? Why?

2. Why are the right and left sides alike herunterladen?

3. In what respects are the two ends alike? In what different? Why?

4. How many somites are there from the anterior end to the girdle microsoft office kostenlos downloaden vollversion deutsch chip? How many under the girdle? How many from the girdle to the posterior end?

5. Where are the setæ located in a somite? How are they distributed over the body?

Suggested drawings.

a. An earthworm, dorsal aspect.

b. An earthworm, ventral aspect.

c. An outline diagram of a cross section, to show the location of the setæ, the blood vessels and the alimentary canal.