378 



is some question as to the defiuiteness regarding the placement of the 

 form in the unattached list. Notes are also added in some other cases. 



The arrangement in the list is according to host families and genera 

 in the sequence used in Brittou and Brown's Illustrated Flora of the 

 Northern States and Canada, supplemented by Engler and Prantl's Natiir- 

 liche Pflanzen-familien in cases where the host is not within the range 

 of the former work. The provisional key precedes this list and follows in 

 this connection. 



KEY TO THE UNATTACHED SPECIES OF AECIDIUM IN NORTH 



AMERICA. 



I. Aecia scattered, arising from diffused mycelium : 



Host belonging to I'rticaceae A. Vibcrtum 10 



Host belonging to Chenopodiacae A. EuroUae 12 



Host belonging to Caryophyllaceae A. Cerastii 15 



Host belonging to Fumariaceae I. Dicentrae 27 



Host belonging to Malvaceae : 

 Aeciospores with thin walls : 

 Peridia fugacious, aecia more or less ('llii)li(iil 



in outline I. liiJicrcuJatiim 48 



Peridia less fugacious, aecia pradically ciicular 



in outline A. sp. 49 



Aeciospores with very thick walls A. intervcniens 50 



Host belonging to Iloloragidaceae 1. Prospinaceae 50 



Host belonging to Boraginaceae 4. Myosotidis 60 



Host belonging to Solonaceae 4. PhysnUdlH 72 



Host belonging to Scrophulariaceae A. CoUinsiac 77 



Host belonging to Valerianaceae A. Valcrianellae 80 



Host belonging to Cichoriaceae 4. Colnmhierise 90 



II. Aecia gregarious, arising from a limited mycelium: 



Host belonging to Scheuchzeriaceae 1. Trif/lochims 1 



Host belonging to Melanthaceae 4. Uvulariae 2 



Host belonging to Liliaceae : 



Of the genus Leucocrinum ^. sp. 3 



Of the genus Anthericum A. sp. 4 



Host belonging to Convallariaceae A. Trillii 5 



