178 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



sporophytic mycelium in these cases. It is probable that cases 

 similar to A. Podophylli will eventually be found. 



Aecia (secondary) unaccompanied by pycnia were found in 

 twenty-four species and undoubtedly occur in other species, were 

 their history known. This brings up the question of the status 

 of the aecium as a distinct unalterable phase in the life history 

 of certain rusts which lack uredinia. 



It has generally been supposed that urediniospores were the 

 only repeating spores in the rusts. The occurrence of repeating 

 aeciospores in Allodiis and Uromycopsis indicate that, while 

 morphologically they are aecidioid, functionally they may be 

 repeating spores. 



All species of the genus are autoecious with one possible ex- 

 ception, A. graminella, a condition which may be said to be 

 typical of rusts with a shortened life cycle. The only known 

 exceptions are afforded by the genera Calyptospora and Gymno- 

 sporangiiim, both of which, with the single exception of Gymno- 

 sporangium nootkatense, lack uredinia also in their life cycle. 



Generic description 

 ALLODUS Arth. Result. Sci. Congr. Bot. Vienne 345. 1906. 



Cycle of development includes pycnia, aecia, and telia with 

 distinct alternating phases; autoecious. Pycnia and other sori 

 subepidermal. 



Pycnia deep-seated, usually globoid or flask-shaped, with 

 ostiolar filaments. 



Aecia erumpent, cupulate or cylindrical, of two sorts, primary 

 and secondary; the primary aecia sometimes giving rise to second- 

 ary aecia unaccompanied by pycnia; the secondary aecia fre- 

 quently followed by the telia. Peridium colorless, dehiscent by 

 apical rupture, the margin lacerate or crose, erect, spreading 

 or recurved. Aeciospores catenulate, globoid or ellipsoid, often 

 angular; the wall colorless or nearly so, verrucose. 



Telia erumpent or long covered by the epidermis, arising either 

 around or from within the secondary aecia and later independently; 

 or arising at first independently from infection by aeciospores 

 from the primary aecia. Teliospores free, pedicelled, two-celled; 

 the wall colored, firm, smooth or verrucosely sculptured. 



Urediniospores rarely found in the telia. 



Type species, Piiccinia Podophylli Schw., on Podophyllum 

 peltaium L. 



