r 



Hes-elmaier Tubingen, Jan. 17,1868 



Rec.Feb.10 



Mbst EObnored Sir Doctor ! 



Be cause the matter has some urgenoy,! annouce to youthe arri- 

 val several days ago of your letter, before I 7 studied its Contents , . 

 and can discuss it. Be convinced, that it will be studied and eva- 

 luated with all conscienciousness. In the raeantirae my heartiest thanks 

 for everything:: for the plant for the valuable contributiorr to my 

 albummof scholar s, always a constant patron- and advisor of my sraalT 

 ef f ort s, and, f inally, for the esteeraed remarks about the life of the 

 Lemnaceae in your area« My last letter, in which I announced the re- 

 ceipt of the plänts in alcoholl crossed in the meantime with your s, and 

 will have arrived about simu Itaneously with yours.. I want to answer 

 now your youngest questions before you trust yourself to the atlan- 

 tic ocean, as far as P am able for the moment , re specti vely add- some 

 from my s i d e • 



Lemna trisulca The sterile sprouts are always without stomata, 

 whereas the flowering ones develop sowe in modest number on theiir 

 surface, which has been known a long time. You will find thera the 

 most likely on the base part (( i.e. that, which forms the pockets- 

 from which 1, the sprouts emerge) ; there, they are never absent, are how- 

 ever not always seen easily due to their small 1 number 1 . On the lower 

 part they are generally even fewer. 



Lemna melanorrhlza is indeed closely related to polyrrhiza , a 

 Splrodela ; I knew it already a long time prior to the descritiorr 

 in the Journal of Seeman. 



Wolf f ia Welwitschii I compared ' with polyrrhiza only as to size 

 (i.e. extension of surface not thickness) and not as to forirr in order 

 to TDrovid;^ for uninitiated ar least some i^ea about the approximate 

 dimensiohs as unusual for a Wolffia ( "magni tudine quod latitudine 

 et longitudine paene cum L . polyrrhiza comparandae* 1 ) . The form is 



