278 BOTANICAL GAZETTE. 



fungus on the leaves alone, it would appear to be the Tilletia 

 bullata of Fuckel, referred by Schroeter in Cohn's Beit, zur 

 Biol., vol. II, p. 355, to Ust. Bistortarum (D. 0.). Prof. Bes- 

 sey's specimens on leaves agree well with Schroeter's description. 

 A question may arise as to the species when we consider its ap- 

 pearance on the flowers. In Ust. Candollei, Tul., closely re- 

 lated to Ust. Bistortarum, the ovaries are distorted so that they 

 project like columns from the perianth, but in the specimens col- 

 lected both by Prof. Bessey and Mr. Halsted, the distortion is 

 still greater. The ovaries are all transformed into more or less 

 globular hard masses and, as nearly all the flowers of a spike are 

 affected, the masses coalesce, forming a compact cylinder with a 

 nodulated surface in which the individual flowers can hardly be 

 recognized. The color of the spores, both in the form on the 

 flowers as well as that on the leaves, is hardly purple but more 

 nearly brownish than in Ust. Candollei. While referring the spe- 

 cies to Ust Bistortarum (D. C), it will be seen that there are sev- 

 eral points in which the American plant does not exactly agree 

 with the European form. The form on the leaves, I would add, is 

 much like Libert Plant. Crypt. Ard., No. 88. 



W. G. Farlow. 



" Thistledown." l 



A STUDY. 



As a child, have you not held gently poised twixt thumb and 

 finger the airy, fleecy thistledown, then lightly blowing watched 

 the tiny parachute as it sailed away? It is a delicate, cunning 

 device, lighter and more buoyant than a bird's feather, smaller 

 and finer than the moth's antennae. 



When separated from the achene, it consists of plumelike fil- 

 aments attached to a ring. Its mode of attachment to the seed 

 is peculiar. The upper end of the achene is grooved, thus leav- 

 ing a small projecting edge of the calyx. Into this groove fits a 

 minute ring — large enough to slip upon a common pin. The 

 pappus is attached to the lower edge of this ring, while over the 

 upper edge fits the corolla and its adhering stamens. The end 

 of the achene — inside the groove — is elongated and to this is at- 

 tached the pistil. 



iFrom the "Aurora" for May, a journal conducted by the students of the 

 Iowa Agricultural College. Miss Knapp is a special student in botany, and in 

 this article gives us a glimpse of the kind of work done by Professor Bessey 's 

 pupils. — Eds. 



