CONTENTS 



i. Clark, Austin H. The present distribution of the Ony- 

 chophora, a group of terrestrial invertebrates. Published 

 January 4, 191 5. 25 pp. (Publication number 2319.) 



2. Reese, A. M. The development of the lungs of the alligator. 



March 3, 1915. n pp., 9 pis. (Pub. no. 2356.) 



3. Angstrom, Anders. A study of the radiation of the atmos- 



phere. September 1, 1915. 159 pp. (Pub. no. 2354.) 



4. Abbot, C. G., Fowle, F. E., and Aldrich, L. B. New evidence 



on the intensity of solar radiation outside the atmosphere. 

 June 19, 1915. 55 pp. (Pub. no. 2361.) 



5. Wherry, Edgar T. The microspectroscope in mineralogy. 



April 19, 1915. 16 pp. (Pub. no. 2362.) 



6. Explorations and field-work of the Smithsonian Institution in 



1914. July 2, 191 5. 95 pp., 1 pi. (Pub. no. 2363.) 



7. Mackenzie, Kenneth K. Two new sedges from the south- 



western United States. April 9, 191 5. 3 pp. (Pub. no. 



2364-) 



8. Maxon, William R. Report upon a collection of ferns from 



western South America. May 3, 191 5. 12 pp. (Pub. no. 

 2366.) 



9. Abbot, C. G. Arequipa pyrheliometry. February 29, 1916. 24 



pp. (Pub. no. 2367.) 



10. Clark, Austin H. A phylogenetic study of the recent crinoids, 



with special reference to the question of specialization through 

 the partial or complete suppression of structural characters. 

 August 19, 191 5. 67 pp. (Pub. no. 2369.) 



11. Parson, A. L. A magneton theory of the structure of the atom. 



November 29, 1915. 80 pp., 2 pis. (Pub. no. 2371.) 



12. Miller, Gerrit S., Jr. The jaw of the Piltdown man. Novem- 



ber 24, 1915. 31 pp., 5 pis. (Pub. no. 2376.) 



13. Mearns, Edgar A. Descriptions of seven new subspecies and 



one new species of African birds (Plantain-Eater, Courser, 

 and Rail). November 26, 1915. 9 pp. (Pub. no. 2378.) 



14. McIndoo, N. E. The sense organs on the mouth-parts of the 



honey bee. January 12, 1916. 55 pp. (Pub. no. 2381.) 



(v) 



