1V CONTENTS 
No. 3... APRIE5S 
HELEN Dean Kino. Studies on sex-determination in Amphibians. V. The 
effects of changing the water content of the egg, at or before the time of 
fertilization, on the sex-ratio of Bufo lentiginosus...................... 319 
Davip Day WuitNey. Reinvigoration produced by cross fertilization in 
Hydatina ‘senta, :.c CaS ele Eien se eee eee EE eae 337 
MaNTON CoPpEeLAND. The olfactory reactions of the puffer or swellfish, 
Spheroides maculatus (Bloch and Schneider)........................... 363 
JOHN CC. PaILLIPss Sizeanheritanceinidicksh semana eee ee 369 
JACQUES LOEB anpD F. W. Bancrorr. Can the spermatozoén develop outside 
theiege? -Bleven figures: ca: ccs Apc erg nee tee ee eee ee eee 381 
Davin H. Tennent. Studies in cytology. I. A further study of the chro- 
mosomes of Toxopneustes variegatus. II. The behavior of the chromo- 
somes in Arbacia-Toxopneustes crosses. Twenty-one figures.......... 391 
No. 4. MAY 20 
Frank R. Liuuie. Studies of fertilization in Nereis. III. The morphology 
of the normal fertilization of Nereis. IV. The fertilization power of por- 
tions of the spermatozoén. Forty-eight figures........................ 413 
T. H. Morean. The elimination of the sex-chromosomes from the male- 
producing eggs of Phylloxerans. Twenty-nine figures.................. 479 
A. H. Sturtevant. An experiment dealing with sex-linkage in fowls. Four 
MeRKEL Henry Jacoss. Studies on the physiological characters of species. 
I. The effects of carbon dioxide on various protozoa.................... 519 
JacquEs LorB AND HARDOLPH WASTENEYS. On the adaptation of fish (Fun- 
dulus)tothigher--emperaturesin. os. 5 te eae ce ec meee einen eee eee 543 
