402 W. H. TALIAFERRO 



upward movement of the card in this case involves an increase 

 in light intensity and as Pecten shows typical reactions only 

 to decreases in intensity, the author is of the opinion that these 

 experiments show that the eye of Pecten may form an image. 



Willis (48) finds that fragments of Amoeba proieus which 

 contain a nucleus exhibit essentially the same type of locomo- 

 tion and orientation to light as do normal specimens. In enu- 

 cleated fragments, however, locomotion is very imperfect and 

 there is no evidence of orientation to a horizontal beam of light. 

 The author is of the opinion that this regulatory influence of 

 the nucleus is " brought about by some sort of an influence 

 upon the attachment of the organism to the substratum." 



REFERENCES 



1 Allee, W. C. The Effect of Certain Ions on Rheotaxis in Asellus. Science, 

 N. S., 43, 142-143. 



2. Allee, W. C. Chemical Control of Rheotaxis in Asellus. Jour. Exp. Zool., 



21, 163-198. 



3. Allen, B. M. Notes on the Spiny Lobster (Pamdirus Jnterruptus) of the 



California Coast. Univ. of Calif. Pub. in Zool, 16, 139-152. 



4. Bovie, W. T. The Action of Schumann Rays on Living Organisms. Bot. 



Gazette, 61, 1-29. 



5. Buddenbrock, W. von. A Criticism of the Tropism Theory of Jacques Loeb. 



Jour. Animal Behav., 6, 341-366. 



6. Gary, L. R. The Influence of the Marginal Sense Organs on the Rate of 



Regeneration in Cassiopea Xamachana. Jour. Exp. Zool., 21, 1-32. 



7. Crozier, W. J. Behavior of Holothuria Captiva Toward Balanced Illumina- 



tion. Science N. S., 43, 148. 



8. Crozier. W. J. The Rhythmic Pulsation of the Cloaca of Holothuriuns. 



Jour. 'Exp. Zool, 20, 297-356. 



9. Crozier, W. J. On a Barnacle, Conchoderma Virgatum. Attached to a Fish, 



Diodon Hystrix. Amer. Nat., 50, 636-640. 



10. Crozier, W. J. On the Immunity Coloration of Some Nudibranchs. Proc. 



Nat. Acad. Sci., 2, 672-675. 



11. Esterly, Calvin O. The Feeding Habits and Food of Pelagic Copepods 



and the Question of Nutrition by Organic Substances in Solution in the 

 Water. Univ. of Calif. Pub. in Zool, 16, 171-184. 



12. Grave, C. The Process of Feeding in the Oyster. Science, N. S., 44, 178-181. 



13. Jordan, H. Ueber " reflexarme " Tiere. IV. Die Holothurien. Zweite 



Mitteilung. Zool. Jahrb., Abt. f. Zool. u. Physiol, 36, 109-156. 



14. Kanda, S. Studies on the Geotropism of the Marine Snail, Littorina liltorea. 



Biol. Bull, 30, 57-84. 



15. Kanda, S. The Geotropism of Freshwater Snails. Biol. Bull, 30, 85-98. 



16. Kellogg, J. L. Opinions on Some Ciliary Activities. Science, N. S., 44, 



852-855. 



17. Lankester, E. R. The Supposed Exhibition of Purpose and Intelligence of 



the Foraminifera. Jour. Roy. Micro. Soc, (1916), 133-137. 



