1916] Index to Volumes I to XXXI 203 



PiCKEii, James Marion vol. page 



Propenyl-iso-toluylen-amidine 8 40 



Pinch-effect in unidirectional electric sparks, Patterson. ... 24 145 

 Pine and its products, industrial and scientific aspects, 



Herty 23 30 



Pine seeds, vitality of, and the delayed opening of cones, 



CoKER 26 43 



Pine, long-leaf, and its struggle for existence, Ashe 11 1 



Pinus serotina, volatile oil, Herty and Dickson 24 101 



Pinus strobus, occurrence in central North Carolina, Holmes 1 86 

 Piperonal condensation with certain aromatic amines, 



Wheeler 29 77 



Plant food constituents, rate of extraction from the phos- 

 phate of calcium and from a loam soil. Bell 26 116 



Plants, flowering, additions to Curtis's catalogue of indi- 

 genous and naturalized plants of North Carolina, Hyams. 2 72 

 Plants growing spontaneously in Henderson County, Mem- 



MINGER 30 126 



Plant breeding, economic, in the cotton belt, Cokeb 24 9 



Plant life of Hartsville, S. C, Coker 27 169 



Plant pathology, Stevens 21 61 



Platinum, occurrence in North Carolina, Venable 8 123 



Plutonic rocks of Chapel Hill, Fry 27 124 



Potash, determination, Dancy 3 37 



Potassium determinations, Adie and Wood method, Basker- 



viLLE and Harris 17 I 18 



Potassium cyanide, decomposition, Wilkes 1 18 



Potassium cyanide, decomposition, Manning 4 I 54 



PoTEAT, William Lewis 



North Carolina desmids — a preliminary list 5 1 



A tube-building spider 6 134 



Notes on the fertility of Physa heterostropha (Say) .... 8 70 

 Pratt, Joseph Hyde 



Notes on North Carolina minerals 14 61 



A review of the chemical constitution of tourmaline as 



interpreted by Penfield, Foote and Clarke 17 II 1 



A peculiar iron of supposed meteoric origin from David- 

 son County, North Carolina 17 II 21 



The southern Appalachian forest reserve 21 156 



Corundum and the peridotites of western North Caro- 

 lina, a review (with J. V. Lewis) 22 8 



The cement gold ores of Deadwood, Black Hills, South 



Dakota 22 23 



The building and ornamental stones of North Carolina, 



a review 22 63 



Recent changes in gold mining in North Carolina that 

 have favorably affected this industry (with A. A. 



Steel) 23 108 



