—74— 



such scheme as this is adopted, we will continue to have 

 described new species of very unequal value. 



The naming of species, sub-species, and forms so that 

 their values may be seen at a glance, is a matter of no 

 little importance. Species, of course, are to have a gen- 

 eric and specific name, and sub-species should have a 

 third name added. How to distinguish the forms from 

 sub-species is the greatest question. There are forms 

 that are due to the season, the soil, the exposure or the 

 geographical position — the elementary species. These 

 should not be named the same as good sub-species. For 

 instance, Onoclea sensibilis obtusilobata is certainly not 

 equal in value to Nephrodium cristatitm CUntonianum. 

 There are many botanists who object to giving these 

 elementary species any name at all, but the manifest ad- 

 vantages to be derived from the use of such names in 

 indicating exactly what plant is meant> inclines me to 

 think all should have a Latin name. If we precede such 

 terms by the word forma, we have probably arrived at 

 a serviceable nomenclature at least. 



OBSERVATIONS ON NORTH AMERICAN 

 PTERIDOPHYTES. 



By B. D. Gilbert. 



Selaginella caribensis Jenm. When Mr. A. A. 

 Eaton was in Florida collecting, in the winter of 1903-4, 

 he sent me, among other things, a little Selaginella, 

 which I did not recognize at the time. I expected that 

 when he went back to the Ames Laboratory he would 

 hunt it up and publish it. He did not include it in his 

 " Preliminary List of Pterldophyta Collected in Florida 

 during November and December, 1903," which was pub- 

 lished in the Fern Bulletin for April, 1904, and I am 

 not aware that it has been published elsewhere. So it is 

 included herewith, as an addition to the Pteridophytes of 

 this continent. It is a delicate Jamaican species, which 

 has found its way to Florida in company with a large 



