136 BOTANICAL GAZETTE [FEBRUARY 
made. The thermal death point was not ascertained, but it is evi- | 
dently much above that of the mycelium grown upon agar (see table 
VI). The fact that new growth, or further growth, did not appear 
upon some of the insects was expected, since sterilization precautions 
could not there be observed, and foreign molds were sometimes pres 
ent.— B. M. Ducear, Cornell University, Ithaca, N. Y. a 
ov 
DESCRIPTIONS OF TWO WILLOWS FROM CENTRAL 
MEXICO. 
(WITH FIGURES I, 2.) | 
THE two willows here described were collected by Mr. Pringle at | 
Sierra de Ajusco in the state of Mexico. They were collected at a 
altitude of 10,000 feet. The descriptions of Mexican willows are me 
ger and imperfect. Anderson in the Prodromus gives them very little ; 
attention, probably having only scanty material from that region, and 
with very little literature from which to make up descriptions. = 
The writer wishes to express his gratitude to Dr. Robinson and Mt 
Greenman of the Gray Herbarium not only for the opportunity * ; 
study the specimens but also for much information regarding the 
Mexican species. 
Salix Pringlei, n. sp.—Shrub 1 to 2™ high: twigs of seasons 
growth minutely hoary puberulent, older shoots dull olive gree? 
? 
2™, on petioles 5™ long; stipules none: pistillate ament er 
nearly sessile in its leafy bracts, 2™ long by 1™ thick, sub 
= 
leaves : mature capsules lanceolate conical on glabrous pedicels: 
This description is based on Mr. Pringle’s no. 6795- Ne . hich 
Plant was collected. The species is related to S. candida W 
