BOOK REVIEW 209 



May June 



Arrival Departure Arrival Departure 



23 Hummingbird 4 Louisiana Water Thrush June 5 



23 White-crownpd Sparrow May 24 13 Yellow-billed Cuckoo 



24 Wilson Warbler June 3 15 Prairie Horned Lark 



24 Canada Warbler June 7 21 Sycamore Warbler June 22 



28 Alder Flycatcher 22 Acadian Flycatcher July 16 



28 Yellow-bellied Flycatcher June 8 



28 Night Hawk Total number of migrants seen, 106. 

 31 Grasshopper Sparrow 



BOOK REVIEW. 



Flora of the Rocky Mountains and Adjacent Plains — Colorado, 

 Utah, Wyoming, Idaho, Montana, Saskatchewan, Alberta, and 

 Neighboring Parts of Nebraska, South Dakota, North Dakota 

 and British Columbia. By P. A Rydberg, New York. Pub- 

 lished by the Author, 19 17.* 



This peaceful work of Sisyphus producing botanical manuals is 

 still going on in the midst of war activities. Dates and facts .are 

 amassed, and new matter is added continually, and the old has to 

 be eliminated all the time for the newer and better. On account of 

 these incessant researches and increased knowledge the life of a 

 manual is naturally short. Nelson's manual was copyrighted in 

 1909 and its successor is forced through by necessity. Before we 

 proceed to review briefly the part of the interwoven text allotted to 

 the flora of North Dakota, one of the "adjacent plains," may I 

 make safe of the author's and the reader's conception, that no word 

 of mine is to be interpreted as a criticism? 



Dr. Rydberg's number of species described is 5897, and varieties 

 are excluded from consideration, no doubt for important reasons, 

 one of them being the desideratum of saving space. This decision to 

 disregard varieties, perhaps without a corresponding liberality in the 

 admittance of species which only would work then as a bomerang, 

 has its inconvenience, which I may illustrate by this instance. 

 Dr. Aven Nelson retained in his manual Arnica julgens as a species 

 with A. pedunculata and A. monocephala as synonyms. If Dr. 

 Rydberg acquiesced in this ranking at first, he presumably changed 

 his mind when he discovered that these latter two species of his 



* Reported here as far as North Dakota is concerned by J. LunEU,. 



