OPEN LETTERS. 
Added synonymy. 
_ In noticing the revision of the N. Am. Alsinez by Dr. B. L. Rob- 
Inson, in the August number of the GazeTTE, was it fair to say that in 
peace” !—Joun H. REDFIELD, Philadelphia, Pa. 
[Naturally no reference was made to the addition of Spergularia to 
synonymy, but to the consequent addition of new binomial combina- 
tions.—Eps, | 
Marchantia as atype. 
Dr. Underwood’s objection to the use of Marchantia as a type in 
morphological courses of study expressed in several places page | 
and reiterated in his vice-presidential address at Brooklyn last mont 
seems to me based upon a misunderstan ing. I use this plant con- 
ot, as D 
rwoo 
address used it to illustrate, viz., the greatest possible complexity of 
thallus. For neither of the other two lines of development, of a 
- 
honored Mar in spite of th 
Marchantia as one of the bryophyte types, in spite of the 
= that it is a representative of only a small group of hepatics and 
at the lowest,-_R. 
