2. Find and sketch a spumellarian radiolarian and a nassellarian radiolarian. Label all the features that you can. What depth is suggested by a sample with mostly spumellarians? With mostly nassellarians?

3. A sample dredged from the sea floor contains agglutinated (but no calcareous) forams and some nassellarian radiolarians. What depth range is the sample from and why? What physical factors are involved?

4. Look at the plaster models of forams (if available) and note the variety of shapes. Try to locate chambers, apertures, and proloculi.

5. Here are some more forams. Locate the specimens on the slides and try to determine test type and suborder:

6. Benthic forams, which live on the sea bottom, tend to have heavy, often compressed-looking tests. By contrast, planktic forams tend to look light and have spherical test chambers. Find and sketch a benthic foram and a planktic foram. How would you account for the difference in test morphology?

Back to Chapter Five.