DEPARTMENT OF BpTANY 



6 January 1897 



loo W I 



}JSy descn I>!r. Davenportf'-f tnrtf I «o# 9<to'^ J 



nrtVi tuirik the Adanson matter is clear at least it is to met 



If Aslmina is a valid genus then others founcled at the saiae time have 

 a- right to be recognizedi a condition and not a theor that confronts 

 us i since some have denied that Adanson's genera should be recognized. 

 Th-en if m'yopteris was duly foimded with any members of vrhat has 

 since been called Aspidium or Lastrea or Nephrodium as its type then 

 Bropterls must hold, no matter what Jaetter characterizations were made 

 of genera eince* vmatever is added to it that comes within the same 

 limits Trill follow into the same genus. 35iat is all I meant by citing 

 other of Adanson's genera; I had supposed you had opposed it because 

 it was Adanson's and hence not as well characterized as later writers 

 have characterized tlieir genera ( S\Tartz e.g. ) The same would be the 

 case with most of the genera described before 1800 and many sincei The 

 fact that a genus is poorljr characterized does no.t affect its validity. 

 Ever,> one who adds a new species to a genvis increases the extent and 

 limits of that genus and to a certain extent renders the generic descri 

 pt Ion faulty ,1.0. If the spec les .is .not closeOj ^j,iQ,d to sone other one 

 already described. •ir<'.»-r'> v"-- v ^n'!- '.'■« r ^•ff j f>» »• - - ^ - . 



I om glad to know yoOT idea of Polystichura. I wish you had express 

 ed it also on Onoclea. I will say fLirthor that I bellove Lawson and 

 John smith were more nestrly right than H,& B. in separating Dennstedtia 

 from Dlcksonla. Sirpely Cibotiiim from the Sandvfich islands has nothing 

 in coTiinion with Dickoonia, and if D.antarctica is a Diclcsonia I :do not 



