Jan. 1908] Cultures of Uredineae in 1907 23 



III. Telia hypophyllous, scattered, round or oblong, 0.2-0.4 mm. 

 wide by 0.3-0.8 mm. long, early naked, dark chocolate-brown, pulvinate, 

 ruptured epidermis noticeable; teliospores clavate-oblong, 12-15 by 35-45 M, 

 rounded or obtuse at apex, usually narrowed below, wall chestnut-brown, 

 concolorous, 1-1.5 m thick, much thicker above, 9-13 /": pedicel about length 

 of spore or less, tinted. 



On Carex longirostris Torr., Wisconsin. 



6. Puccinia mutabilis Ellis & Gall. While collecting for 

 a few days in Colorado about the first of May, wintered-over 

 teliospores were found on a number of species of Allium, in 

 most cases not accurately determined for want of the inflores- 

 cence. In a few cases young leaves of the season showed freshly 

 formed uredinia, and in one instance immature telia were ob- 

 served beside the uredinia, evidently arising from the same 

 mycelium. A few very young aecia, well isolated from other 

 spore forms were also found. As it was clearly too early in the 

 season to have had aecia mature and reinfect the host, and in 

 this manner give rise to the uredinia, the question arose whether 

 the aecia did not belong to some heteroecious species, while the 

 uredinia and telia represented a species without aecia. Further 

 search in the field brought to light some leaves which without 

 question had remained alive over winter. In one case the dead 

 tip of such a leaf bore telia of last year's growth, and on the 

 adjoining green part of the leaf uredinia were forming. This 

 seemed to show that the early uredinia were derived from 

 wintered-over mycelium, but it left the question of the origin 

 of the aecia unsolved. 



Teliosporic material on what was believed to be Allium 

 rcticulatum Fraser, was obtained by the writer at Eldorado 

 Springs, Colo., and sown on Allium recurvatum Rydb., May 18, 

 giving rise to pycnia June 3, and aecia June 7. The life cycle 

 of the rust with all spore forms is therefore established, although 

 it is clearly possible in exceptional cases for the mycelium to be 

 carried over the winter in leaves that retain their vitality and thus 

 start the rust in the spring at the uredinial stage. 



7. Gymnosporangium Betheli Kern. Teliosporic ma- 

 terial on Juniperus scopulorum Sarg., obtained at Boulder, 

 Colo., by Mr. F. D. Kern, was sown on Crataegus sp. (re- 

 ceived from the Arnold Arboretum) April 30, showing pycnia 

 May 8, and aecia June 5, the aecia being fully matured by June 

 17. Another sowing was made on Crataegus coccinea May 15, 

 snowing pycnia May 21, and aecia June 24. Another sowing 

 on Crataegus punctata May 15, gave pycnia May 21, but the 

 leaves withered before aecia had formed. Another sowing on 

 Sorbus Americana May 21, gave rise to numerous pycnia May 

 29, and an equal abundance of well formed aecia July 25. 



