PAPERS GIVING RUSTS OF NORTH AMERICA. 237 



longer leaf, mounted loose in a packet bearing five large, circinating 

 groups of ascia, and by a small fragment of leaf about 3 cm. long, 

 bearing secia, in the original packet, labelled inside " Roestelia oxy- 

 acanthse a in Crat. oxyacant prope Philadelphia," and above this 

 written later " Caeoma cylindrites," and labelled outside " 2 Cseoma 

 (Ceratites) cylindrites oxyacanthse in Hedgerows Philad. vulgatis- 

 sima." 



This secial rust observed by Schweinitz to be very common, on 

 what was doubtless the English hawthorn (Cratccgus Oxyacantha 

 L.) and thought distinctive, was not again recognized until a trip by 

 Dr. Frank D. Kern and the senior author to South Carolina in 

 March, 1910, brought it to light. It belongs to Gymiiosporangiwn 

 trachysoriim Kern, having telia on Juniperus virg'miana. 



8. Represented by one large, 5 cm. broad, and originally 10 cm. 

 long, strongly pubescent leaf of the cultivated apple, bearing numer- 

 ous small groups of secia, one half, 4 cm. long, being mounted, and 

 the other half, 5 cm. long, in the original packet, which is labelled 

 inside " Roestelia cancellata In Pyro coronario Salem," with all but 

 the first word afterward crossed out, as if it were an error, and "/? 

 penicillatum var Mali " substituted, and added below " var. in Malo 

 Bethl," and still later there was written above " Caeoma cylindrites," 

 while on the outside the packet was labelled "2 Caeoma (Ceratites) 

 cylindrites fi penicillat in Pyr. Malo Beth." 



The rust proves to be the secial stage of Gyinnosporangium 

 Juniperi-virginiancc Schw. and on the common apple Mains Mains 

 (L.) Bntton (Pyrus Malus L.) . 



The entry in the North Carolina list, no. 432, is not represented 

 by a specimen, and is too indefinite to be associated with any certain 

 species, unless the form ^ be considered to cover it. 



2900. 90. C. R. Roestelites, Lk. 173. ^cid. cancellatum, Syn. Car. 433 

 [error for 431]. In Bethlehem in an old orchard rejoicing in 

 huge trees of Pyrus malus. In late autumn I have seen some of 

 these trees, for 6-7 years, so covered by this fungus that the 

 leaves appear red from a long distance. 

 (431. 2. [/Ecidium] cancellatum. Very rare, only once on pear 

 leaves.) 



Represented by two sets of very unlike leaves, part of each beino- 



PROC. AMER. PHIL. £OC., VOL. LVII, Q, JULY 17. I918. 



