Durieu recognized a 3rd species in a unique sample from the herbarium in Philadelphia. 

 He informed us of this and we sent it back. It cornes from the Catskill mountains and 

 New York. We do not know who collected it. 



A fourth species is found in Clinton, lowa from where it was sent to Gray by Dr. George 

 Vasey under the name of Isoetes Engelmanni. In Athens, III. it was also found and 

 collected by Mr. E. Hall who wrote about it to our friend Durand. It had the same name of 

 Isoetes Engelmanni. I have a sample sent by Gray and I have shared with Durieu the 

 5 samples sent to me by Durand. It is the only North American species known until now 

 that is in water only in the winter, but lives at the other times of the year, completely dry 

 and does not bare fruit until the water recèdes completely. It has no similarity with the 

 Isoetes Engelmanni as was described by Braun, nor with the Engelmanni from 

 Wilmington, Delaware and the environs of Philadelphia. It is very remarkable among 

 other things, because of its macrospores, that I believe are smooth ( laeves, tuberculis, 

 carentes), and by its foliaceous bases that are colored a strong shiny brown; this, one 

 does not see in any other species, on living leaves. This species is surely new and I will 

 describe it under the names of Isoetes melanopoda. Durand wrote me that he reported 

 thèse plants to you but that he has never received your opinion. 



lowa and Illinois in the west on either side of the Mississippi is the land of the prairies, it 

 is a land of particular characteristics and which I believe spreads ail the way to your St. 

 Louis. Therefore it is not at ail astonishing that it should have its particular type of 

 Isoetes. But which is the extent of its géographie distribution? Does it exist only in that 

 région or is it in various? You, my dear Doctor are better situated than anyone to study 

 thèse questions, and I hope you will have the honor of resolving them. 



From the southwest of the United States we go to the northeast, Massachusets, New 

 Hamshire, etc. We find a région that also seems to have certain types of Isoetes, of 

 which only one is more or less known well here. It was found last year in Boston by Mr. 

 W. Booth in Boston in a small lake called Horn Pond a few miles from Cambridge, 

 mostly in the small rivers that enter and that exits the lake. It lives completely 

 submerged durins ail seasons, which is not the case of the riparia, Engelmanni nor the 

 inclanopoda. It is a type which is nearly identical with the Isoetes echinospora 

 europea, with its finely bristled macrospores ( non tuberculous), but according to the 

 observations of Durieu, seems to be specifically distinguished, because of its 

 microspores. Thanks to Gray and Booth we have it dried and living. Durieu grew it in 

 Bordeaux, where it is presently happily prospering. 



The northeast of your country is nearly unknown to you. In 1856 you took a trip (was it 

 that year?), and in 2 lakes of New Hamshire, Echo Lake and Winnepesanga, you found 

 two Isoetes which you thought belonged to two differet species: the real pelustres in 

 Lake Echo and the riparia in Lake Winnepesanga. You sent both plants to Al. Braun, 

 who published nothing about their state in the herbarium, in which I have not seen them. 



From the plant of Echo Lake that you sent me ( in your letter of February 20 1862) with a 

 sample in poor condition, that is now in the hands of Durieu, nor he nor I were able to 

 see anything. Therefore I have under my eyes a better sample, collected last year in the 

 same Echo Lake, by Mr Booth from Boston. That one has nothing to do with the Isoetes 

 lacustre and is exactly the plant from Horn Pond, of which I spoke to you in the previous 



