122 Rydberg: Notes on Rosaceae 



Ruhus with Linnaeus should be R. idaeiis, and if I had separated 

 the raspberries and blackberries generically, I would have adopted 

 Ruhus as the generic name of the former. Dr. Greene does not 

 accept the Linnaeus Species Plantarum as the starting point of 

 botanical nomenclature, and on that ground probably had valid 

 reasons for a different interpretation. The validity of the pro- 

 posed species of Batidaea I shall discuss later. 



Melanohatus Greene has no foundation as a genus separate 

 from Batidaea. The only characters given by Greene distinguish- 

 ing the two genera are the pulp of the fruit and the reticulation of 

 the pyrenes. The former is said to be soft, very juicy and perish- 

 able in Batidaea and scanty, firm rather than watery, in Melano- 

 hatus. Ruhus idaeus aculeatissimus of Siberia according to Focke 

 has almost dry fruit. Regarding the keel on the back of the 

 putamen, it is not very prominent in R. leucodermis and not found 

 at all in R. Pringlei Rydb. {R. occidentalis grandiflorus Focke). 

 The leaves are said to be "pinnately (rarely pedately) 3-5- 

 foliate." As far as I know, whenever the leaflets are more than 

 three in the black raspberries, the leaves are pedately compound 

 with the terminal leaflet long-petioluled. Someone may ask the 

 question if this also applies to Melanohatus neglectus (Peck) Greene 

 and Melanohatus michiganus Greene. No, not always, but these 

 I understand as forms of R. occidentalis X strigosus* and the 

 occasional pinnately five-foliolate leaves are an inheritance from 

 the other parent, R. strigosus. 



Paramena Greene has R. spectahilis Pursh for the type. This 

 can not be separated generically from the other raspberries. It 

 is closely related to R. rosaefolius, although this relationship has 

 not been pointed out so far as I know. There are all kinds of 

 gradations between the R. rosaefolius group and the R. idaeus 

 group. 



Cardiobatus Greene was based on Ruhus nivalis Dougl. No 

 character of generic value has been pointed out by Dr. Greene. 

 He himself stated: "Technically, a true blackberry" [I do not 

 know if it has a fleshy receptacle, but I doubt it]. The best 

 character to separate it from the dewberries is the broad, almost 



* The hybridity of R. neglectus is satisfactorily proven, as the hybrid has been 

 produced artificially and does not differ from the wild plant. 



