TABLE OF CONTENTS OF VOL. XI 



Page. 



1. — Wilson, E. B. Considerations on Cell-Lineage and 



Ancestral Reminiscence, based on a Re-examina- 

 tion of Some Points in the Early Development of 

 Annelids and Poly clades. (Figs. 1-7), .... i 



2. — Trowbridge, C. C. An "X-Ray Detector" for Re- 



search Purposes. (Figs. 8— 11), 29 



3. — Trowbridge, C. C. The Use of the Fluoroscopic 



Screen in Connection with Rontgen Rays. (Figs. 



12-14), 39 



4.— Lloyd, Francis E. On Hypertrophied Scale-Leaves 



in Pinus ponderosa. (Plate I), 45 



5.— Hollick, Arthur. Notes on Block Island. (Plates 



n-ix), 55 



6.— Dudley, P. H. The Use of the Dudley " Stremma- 

 tograph " in Determining Stresses in Rails under 

 Moving Trains. (Plates X-XIII), 89 



7. — Weller, Stuart. Descriptions of Devonian Crinoids 

 and Blastoids from Milwaukee, Wisconsin. (Plate 

 XIV), 117 



8.— Huntington, Geo. S. The Eparterial Bronchial Sys- 

 tem of the Mammalia. (Plates XV-XXVIII), . 127 



9.— Stevenson, J. J. The Debt of the World to Pure 



Science. Annual Address of the Retiring President, 177 



10. — Griffin, B. B. Description of Some Marine Nemer- 



teans of Puget Sound and Alaska. (Figs. 15-24), 193 



11.— Crampton, H. E., Jr. An Important Instance of In- 

 sect Coalescence, 219 



