ON ADOXA 161 



On Adoxa Moschatellina. March — May. Not uncommon. 

 All parts of the plant are affected, rhizomes, 

 petioles, leaves, peduncles and flowers. 

 (Fig. 112.) 



Puccinia Adoxae and the secidium of P. albescens 



(q.v.) are about equally common, but are rarely 



found together ; they occur not only on different „. 



, . A ii i • -a i + i i r Fig- 112- P. Adoxae. 



plants, but usually also in widely separated locali- Teleutospores 



ties. In fact, it is agreed by all observers that there 



are three cases, (1) where the secidium alone occurs, (2) where the teleuto- 

 spores alone occur, and (3) where they both occur together ; in the latter 

 case uredospores are found with the teleutospores in the same sorus. The 

 first is considered to be the secidium of P. argentata (q.v.), the second is 

 P. Adoxae, and the third is P. albescens. 



Soppitt first proved that the teleutospores of P. Adoxae, laid upon 

 healthy plants when in active germination after passing the winter, 

 reproduce the teleutospores in about ten days without the intervention of 

 other spore-forms. It is therefore a Micropuccinia. Whether the wide- 

 spreading mycelium is perennial or not is uncertain. Worth. G. Smith 

 raised seedlings of Adoxa from berries of an infected plant ; the seedlings 

 exhibited the Puccinia from the earliest stages of growth, but we are not 

 told what precautions were taken to prevent infection from outside. He 

 also found (I.e.) teleuto-sori, in a state of nature, on fusiform swellings 

 of the underground parts of the plant (peduncles and petioles), as also on 

 rhizomes and scales, in March ; the spores were irregular, one-, two-, or 

 three-celled. In April the leaves, and in May the flowers and young 

 fruits were infected. No mycelium could be found in the rhizome. If 

 Plowright's ascription of a perennial mycelium is incorrect, the infection 

 must have first taken place, in this instance, underground on the young 

 growth, and the mycelium gradually spread upwards. That this is 

 probably the case is shown by Fischer's experiment ; he kept plants which 

 had borne teleutospores in pots — if he removed all the leaves, they 

 produced healthy growth next spring, whereas, if the leaves were left on 

 and allowed to fall upon the soil, one plant at least (out of four) showed 

 teleutospores on the new shoots. Bubak inclines to the same opinion 

 (Centralbl. f. Bakt. 2. xvi. 150). 



As will be seen from the synonymy, P. Adoxae and P. albescens are 

 united (under the former name) in Sydows' Monographia, while Soppitt,. 

 Plowright, Bubak and Fischer consider them distinct. In any case they 

 are very closely allied ; the probability is that P. Adoxae is a mutation 

 from P. albescens which has acquired the habit of reproducing teleutospores 

 from teleutospores directly, while the original species from which it was; 

 evolved still maintains all the three spore-forms, though two of them are 



G. U. 11 



