127 



M. A. DESEGLISE'S EEYISIOl!^ OF THE SECTIOI^r TOMENTOS^ 



OE THE GENUS ROSA. 



By Chas. p. Hobkirk. 



Our English, botanists will hail mth. pleasure the appearance of this 

 long-promised work of M. Deseglise on the above section of Rosa. The 

 confusion which has long existed with regard to the Rosa tomentosa of 

 Smith, is now in a fair way of being removed, if it be not altogether cleared 

 up. 



It is not my intention however to wite a Critique upon this review 

 but rather to present to the readers of the Naturalist some of the most salient 

 points in it, more particularly as regards our English, forms, and thus to 

 enable those who are not in possession of the original, to compare the forms 

 that come under their notice, with the diagnoses of the French forms. 



M. Deseglise opens his review with, a quotation from M. Jordan, to 

 wliich I can give my most hearty concurrence : — 



If, in a series of species forming a natural group, we compare the first 



"of the series with the last, we shall doubtless find that they may be very 

 easily distinguished, whilst if we compare tbe fii'st with the second, we shall 

 often be more strvick mth the resemblances than with the difterences wliich 

 exist between them. We ought not however, on this account to unite 

 them ; for if we adopt this plan, we must also unite that which immediately 

 follows, to the second, and so on to the last in the series ; and yet this 

 re-union of the species of a group, into one single species, vicious as it may 

 seem is nevertheless a logical sequence." t 



Again, M. Deseglise writes, (p. 6) ; — If the modern school be open to 

 reproach for being too ready in establishing species, often on a single difier- 

 ence, the same reproach may be applied with equal force to the reducers, 

 who deny such differences without examination ! We must obtain a correct 

 idea of the actual state of things, and work with perseverence and method, 

 for the purpose of obtaining a knowledge of but a part of the objects 

 which lie at our very doors. Is not nature a better guide than Man^ 



• We may have different opinions upon sjpedes, but that should not prevent 

 us from studying to the bottom all the forms which nature presents to us ; 

 they must be analysed, characterised, classed, waiting until science shall 



. decide the rank that these forms should occupy in our classification." 

 t Jordan, Obs. fragm. 6, p. 31. 



