CONTENTS. 
No. 1.— Contributions from the Zoölogical Laboratory. XXVIII. Observa- 
tions on Budding in Paludicella and some other Bryozoa. By C. B. 
DAVENPORT. (12 Plates.) December, 1891 
No. 2. — Contributions from the Zoölogical Laboratory. XXIX. The Gas- 
trulation of Aurelia flavidula, Pér. & Les. By Frank Smirnu. (2 Plates.) 
December, 1891 
No. 3. — Contributions from the Zoölogical Laboratory. XXX. Amitosis in 
the Embryonal Envelopes of the Scorpion. By H. P. Jonnson. (8 Plates.) 
January, 1892 
No. 4. — A Fourth Supplement to the Fifth Volume of the Terrestrial Air- 
Breathing Mollusks of the United States and Adjacent Territories. By 
W. G. Binney. (4 Plates.) January, 1892 
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