NOTES AND ABSTEACTS. 



663 



characters have been maintained both after root multiphcation and in 

 reproduction by seed, as far as this last has been able to be carried 

 out. Further, he declares that among the numerous varieties of the 

 cultivated potato no variation affects any specific character, and no 

 seedling has ever shown any absolute new character. What are pro- 

 duced are merely new combinations of characters already known 

 among older varieties, and the variations are due to the hybrid 

 character of the parent, and not to mutation. No cultivated variety of 

 potatO' will breed true by seed and is only reproduced by division. 



He concludes, therefore, contrary to the opinion of some writers, 

 that it is not by any means proved that S. Commersonii or S. Maglia 

 has ever passed into the cultivated potato, or that these three — 

 S. Commersonii, S. Maglia, and S. tuberosum — have ever converged 

 into similar forms. It would be well to follow up successive genera- 

 tions of *S'. tuherosum from seed, so as to arrive at a pure strain of 

 fixed character, both to throw light on the pedigree of the cultivated 

 potato and perhaps to give new life to strains which may have 

 degenerated by too prolonged and asexual multiplication. — M. L. H. 



Powder Post Beetles of the Family Lyctidae of U.S.A. and 

 Europe, A Revision of the. By E. J. Kraus {U.S.A. Dep. Agr., 

 Bur. Entom., Bull. Tech. ser. xx. pt. in.; May 1911). — The family 

 Lyctidas is represented in North America by certain species of special 

 economic importance as causing injury to seasoned wood products 

 known as "powder post." These species have been the subject of 

 extensive investigations by the writer and his associates to determine 

 their habits, history, and methods of control. There is an appendix 

 by A; D. Hopkins with a list of described species. — V. G. J. 



Primula obconica, The History of, under Cultivation. By 



A. W. Hill (Jour. Gen. ii. p. 1; Feb. 1912; plates).— The history of 

 Primula ohconica since it was introduced in 1879 by Maries up to the 

 present time, tracing the various forms it has assumed under cultiva- 

 tion and comparing them with the wild type. The evidence points 

 to the fact that all the varieties now in cultivation have been derived 

 through careful selection. No attempts at hybridizing have apparently 

 been successful, although several have been made. — F. J. C. 



Races, Geogrraphical, with Partly Fixed and Partly Vari- 

 able Characters. By Viviand-Morel {Rev. Hort, d'Alg. p. 412 ; 



Dec. 1911). — The first of a series of articles on the well-marked 

 variations which appear among the species of plants which are in- 

 digenous over a widespread area. These variations appear as the 

 distinguishing peculiarities of "geographical races," such variations 

 being evidently produced by environment and not the result of hybridi- 

 zation. Some typical examples of such geographical races have been 

 collected and transplanted, and during the time they have been under 

 observation so far the "variations have persisted under cultivation. 

 They also reappear in succeeding generations of annuals, but opinions 



