210 A. Barclaj—BescripHve List of the Ui-odineas [No. 2, 



those of the former. Moreover, the latter is a Leptopticcinia without 

 nredospores. On the other hand, the uredospores of the foimer are 

 somewhat Larger than those I have described above, and the European 

 species is associated with an autoeoious cecidium, which we never find in 

 Simla. Another difference in the Simla species is that the spore beds 

 are always isolated, small, and circular, whilst those of P. Oalii have a 

 tendency to coalesee into irregular masses. 



9. PticciNiA AcETOSiE, Sohum. 

 on Smmex nepalensis, Spr. 



This fungus is very common in Simla and is chiefly remarkable 

 for an apparent lichenoid symbiosis between the mycelium and the 

 chlorophyll-containing cells of the host, such as is described by Dr. D. 

 D. Cunningham, F. R. S., in Bavenelia* 



The areas of the leaf blade invaded by the mycelium remain bril- 

 liantly green long after the rest of the leaf is yellow. The parasite 

 is first met with in October, when the leaves may be seen to bear dark 

 brown minute circular pustules, often with a distinctly circinate ar- 

 rangement, both on the upper and lower surfaces, often in extraordinari- 

 ly large numbers. At this time, if the spores be examined, they will bo 

 found to consist of round or oval single-celled bodies of a pale brown 

 colour measuring from 24 /* in diameter to 28 x 21 /x. These spores are 

 easily detached from their beds without any portion of the stalk adher- 

 ing as a rule. They have a fairly stout epispore beset witli well marked 

 warts, and are thickened very slightly at the free end (Fig. 13, PI. XII). 

 The contents are sometimes finely granular throughout, but 'frequently 

 several oil globules are found in the granular protoplasm. These are 

 uredospores, and they germinate readily in water, throwing out very long 

 simple germ tubes. I have found uredo pustules with a few teleuto- 

 spores in them in March on green leaves, and the spores from them 

 germinate very readily. I do not know whether these pustules had 

 developed recently, or whether they had remained over from the previous 

 autumn. My impression is that they were of quite recent formation. 

 Later, the same pustules produce jjaccMtOT, which arc brown, rounded, and 

 with little or no constriction at the septum (Fig. 13, PI, XII). These 

 spores are very readily detached from their beds, breaking off with only 

 a minute fragment of the stalk adhering. They have a characteristic 

 knob-hke thickening at the free end. The total length of the moisten- 

 ed spores varies from 4.0 to 32 /x, and the breadth at the septum from 18 to 



* On a now Genu, of the Family UMa.ine., ' Soicntiflc Momou-s by Medical 

 Officers of the Army of ludia,' Part III, p. 31. 



