No. 3 — March, igo8 



GiLMAN A. Drew 



The Physiology of the Nervous System of the Razor-Shell Clam (Ensis 

 directus, Con.) With One Plate 311 



Florence Peebles 



The Influence of Grafting on the Polarity of Tubularia. With Twenty- 

 six Figures 327 



N. M. Stevens 



A Study of the Germ Cells of Certain Diptera, with Reference to the 

 Heterochromosomes and the Phenomena of Synapsis. With Four 

 P'^tes ■ 359 



Ralph S. Lillie 



Momentary Elevation of Temperature as a Means of Producing Artificial 



Parthenogenesis in Starfish Eggs and the Condition of its Action 375 



Thos. H. Montgomery, Jr. 



The Sex Ratio and Cocooning Habit of an Aranead and the Genesis of 

 Sex Ratio. With Two Figures 429 



s/ No. 4 — June, igo8 



N. M. Stevens 



The Chromosomes in Diabrotica vittata, Diabrotica soror and Diabrotica 

 l2-punctata. A Contribution to the Literature on Heterochromosomes 

 and Sex Determination. With Three Plates 453 



Victor. E. Emmel 



The Experimenal Control of Asymmetry at Difl^erent Stages in the Devel- 

 opment of the Lobster 471 



C. M. Child 



Physiological Basis of Form-Regulation. With One Figure 485 



H. H. Newman 



The Process of Heredity as Exhibited b\- the Development of Fundulus 



Hybrids. With Five Plates and Sixteen Figures in the Text 503 



C. C. Guthrie 



Further Results of Transplantation of Ovaries in Chickens. With Three 

 T'igures 563 



H. S. Jennings 



Heredity, Variation and Evolution in Protozoa. With Twenty-two 



Figures 577 



