110 



PROCEEDINGS OF THE ACADEMY OF 



[March, 



In table 3 the Orchidaceae found in the Middle States are tabu- 

 lated in a similar way. The article on this family previously pub- 

 lished by the writer^^ included the same species, only two (marked 

 by an asterisk) having been since observed, but the acidity data 

 were given numerically, and no optimum reaction was indicated. 

 In the present table, the reactions are shown graphically, the opti- 

 mum point is indicated as with the Ericaceae, and several extensions 

 of range found as the result of many tests made since the publica- 

 tion of the other paper are included. 



Table 3 



Reactions Relations of Orchidaceae Studied 



Specific acidity 

 300 100 30 

 Medi- Sub- 

 acid acid 



Cypripedium candidum 



])arviflorum x X 



var. pubescens x X 



hirsutum 



acaule X X X 



Orchis (Galeorchis) spectabi- 



lis . X 



Habenaria (Blephariglottis) 



blephariglottis X 



ciliaris X 



cristata X 



fimbriata (grandiflora).. . 



lacera x 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X X 

 X X 



X X 



X X 



X 



X 

 X 

 X 

 X 

 X 

 X 



peramoena 



psycodes X 



(Coeloglossum) bracteata 



(Gymnadeniopsis) clavellata. X 



Integra* - X 



nivea x 



(Lysias) orbiculata 



(Peruaria) flava X 



Limodorum tuberosum X 



Arethusa bulbosa X 



Pogonia ophioglossoides X x x 



divaricata* X x 



(Triphora) triantho- 



phora . X- 



(Isotria) verticillata. ... X X X 



Ibidium beckii X X X 



cernuum x x X 



gracile x X X 



plantagineum (latifolium . x X 



odoratum x X 



praecox x x X 



vernale X XX 



10 3 

 Minim- 

 acid 



Specific alkalinity 

 1 3 10 



N Minim- 



alk. 



X 

 X 



o 

 x 



X 



X 

 X 

 X 



X 



X 



o 



X 

 X 



X 

 X 



X 

 X 

 X 



X 

 X 



o 



X 



X 



X 



X 



X 

 X 

 X 



X 



X 

 X 

 X 

 X 



X 

 X 

 X 

 X 



^^Journ. Wash. Acad. Sci. 8, 590-598, 1918. 



