CONTENTS 
1910 
No. 1. MARCH 
Bennet M. AuLeEN. The origin of the sex-cells of Amia and Lepidosteus. 
went y-SeMmel os MEMTESs 2/32 4. u.s hiner Ohad eee ore, ches cas A ee eS 1 
Leo Lorns. The cyclic changes in the ovary of the guinea pig................ 37 
Epmunp B. Witson. Studies on chromosomes. VII. A review of the 
chromosomes of Nezara; with some more general considerations. Nine 
figuines: *One- plates soar fied os et Soke Me a Ao ee eas he Sade 71 
C. B. Davenport. The transplantation of ovaries in chickens............ 111 
W. J. Morenxuaus. The effects of inbreeding and selection on the fertility, 
vigor and sex ratio of Drosophila ampelophila.......................... 123 
G.H. Parker. The mechanism of locomotion in gastropods. One figure..... 155 
No. 2, JUNE 
C.M.Cuitp. The regulatory processes in organisms.......:............... 171 
LoRANDE Loss WoopruFFr. Paramecium aurelia and Paramecium caudatum. 
POUL GG UN ELIT ye at goles Sao, anata Mie sa ee Re et Ph 50 a 223 
EK. A. ANDREWS. Male organs for sperm-transfer in the crayfish, Cambarus 
affinis; their structure and use. Four plates and thirty-one text figures... 239 
WALLACE CraiGc. Oviposition induced by the male in pigeons............... 299 
WixLu1aM Morton WHEELER. The ant-colony as an organism............... 307 
Giuman A. Drew. Sexual activities of the squid, Loligo pealii (Les). Four 
Obese oe ne eee ae ote ete BORA ek ote armel le oak |e ee 327 
Frank R. Litire. Studies of fertilization in Nereis. I. The cortical changes 
in the egg. II. Partial fertilization. One double plate................. 361 
W.E. Ritrerand Myrtie EK. Jonnson. The growth and differentiation of the 
chain of Cyclosalpa affinis (Chamisso). Four plates.................... 395 
Oscar Rippie. On the formation, significance and chemistry of the white 
and yellow yolk of ova. Three plates................ Oe one ae 455 
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