CONTENTS 



PAGES 



1. An outliue of the Morphology aud Life History of Crithidia lepto- 



coridis, sp. nov., by Irene McCulloch ; with plates 1-4 ; one figure 



in text 1-22 



2. On Giardia microti sp. nov., from the Meadow Mouse, by Charles 



Atwood Kofoid and Elizabeth Bohu Christiansen ; one figure in text 23-29 



3. On Binary and Multiple FLssion in Giardia muris (Grassi), by Charles 



Atwood Kofoid and Elizabeth Bohn Christiansen ; with plates 5-8 ; 



one figure in text 30-.54 



4. The Cultivation of Tissues from Amphibians, by John C. Johnson ; 



two figures in text 55-62 



5. Notes on the Tintinnoina: 1. On the Probable Origin of Dictyocysta 



tiara Haeckel ; 2. On Petalotricha entzi sp. nov., by Charles Atwood 

 Kofoid; eight figures in text 63-G9 



6. Binary and Multiple Fission in Hexamitus, by Olive Swezy; with 



plates 9-11 71-88 



7. On a New Triehoraonad Flagellate, Trichomitiis parvxis, from the 



Intestine of Amphibians, by Olive Swezy; with plate 12 89-94 



8. On Blepliarocorys equi sp. nov., A New Ciliate from the Caecum of 



the Horse, by Irwin C. Schumacher; with plate 13 95-106 



9. Three New Helices from California, by S. StUlman Berry 107-111 



10. On Trypanosoma triatomae, a New Flagellate from a Hemipteran 



Bug from the Nests of the Wood Eat Ncotoma fuscipes, by Charles 

 Atwood Kofoid and Irene McCulloch; with plates 14-15 113-126 



11. The Genera Monooercomonas and Polymastix, by Olive Swezy; -ivith 



plates 16-17 127-138 



12. Notes on the Spiny Lobster (Panulirus interrupius) of the California 



Coast, by Bennet M. Allen; two figures in text 139-152 



13. Notes on the Marine Fishes of California, by Carl L. Hubbs; with 



plates 18-20 153-169 



14. The Feeding Habits and Food of Pelagic Copepods and the Question 



of Nutrition by Organic Substances in Solution in the Water, by 



Calvin O. Esterly; two figures in text 171-184 



15. The Kinetonucleus of Flagellates and the Binuclear Theory of Hart- 



mann, by Olive Swezy; fifty -eight figures in text 185-240 



16. On the Life-History of a Soil Amoeba, by Charlie Woodruff Wilson; 



with plates 18-23 241-292 



17. Distribution of the Land Vertebrates of Southeastern Washington, 



by Lee Raymond Dice; with plates 24-26 293-348 



18. The Anatomy of Heptanchits maculatus. The Endoskeleton, by J. 



Frank Daniel; with plates 27-29; eight figures in text 349-370 



19. Some Phases of Spermatogenesis in the Mouse, by Harry B. Yocum ; 



with plate 30 371-380 



20. Specificity in Behavior and the Relation Between Habits in Nature 



and Reactions in the Laboratory, by Calvin O.- Esterly 381-392 



21. The Occurrence of a Rhythm in the Geotropism of Two Species of 



Plankton Copepods when Certain Recurring External Conditions 



are Absent, by Calvin O. Esterly 393-400 



22. On Some New Species of Aphroditidae from the Coast of California, 



by Christine Essenberg; with plates 31-37 401-430 



23. Notes on the Natural History and Behavior of Emerita analoga 



(Stimpson), by Harold Tupper Mead; one figure in text 431-438 



24. Ascidians of the Littoral Zone of Southern California, by William E. 



Ritter and Ruth A. Forsyth; with plates 38-46 439-512 



