INDEX. 41o 



Subgen. 3. Cylindropuntia, 302. 



acanthocarpa, 308. 



arborescens, 307. 



arbuscula, 309. 



Bigelovii, 307. 



bulbispina, 304. 



clavata, 302. 



Davisii, 305. 



echinocarpa, 305. 



Emoryi, 303. 



frutescens, 309. 



fulgida, 306. 



Grahami, 304. 



mamillata, 308. 



Parryi, 303. 



prolifera, 306. 



ramosissima, 309. 



Schottii, 304. 



serpentina, 306. 



stellata, 307. 



tessellata, 309. 



Thurberi, 308. 



vaginata, 309. 



Whipple!, 307. 



Wrightii, 308. 

 Original diversity of the human races, 108. 

 Origin of the human race, diversity of, 7. 

 Orthagoriscus Mola, 319. 



P. 



Peirce, Benjamin. On the form assumed by elastic sacs containing 

 fluid, 8. Observations on photographic images, 9. On the Erics- 

 son engine, 28, 31. On collision of solid bodies, 67. On relations 

 of curves, 83. 

 Peirson, Dr. Decease of, 38. 

 Pelea, 50. 



auriculcefoUa, 50. 

 ' clusicefolia, 50. 

 lucida^ 51. 



