368 A. Barclay — List of the Uredinese occurring [No. 3, 



thickened, and tlie cells of the host are filled densely with starch grains. 

 The spermogonia are situated mostly on the upper surface of the leaf, 

 though some are borne also on the under surface. They are of the 

 usual structure, well sunk into the tissue of the host, and with a tuft 

 of paraphyses protruding from their mouths. These organs generally 

 measure about 0*198 to 0'151 m.m. in depth and 0'138 to 0.126 

 m.m. in width, the tuft of paraphyses measuring about 75 /x, in length. 



Bemai'ks. — There can be no doubt, I think, that this is identical 

 with Puccinia Graminis as described by De Bary, although I have not 

 confirmed its genetic relationship with the Puccinia on cereals which 

 occurs very abundantly in all the fields around Simla. I am also not 

 quite certain that all the three forms of Berberis which occur in Simla 

 (namely, B. vulgaris, L., and B. Lycium, Royle, in addition to that al- 

 ready mentioned) bear the same species of ^cidium. The subject is 

 one which requires further investigation and I will therefore leave it at 

 present an open question. 



12. — ^ciDiuM Urticjs, Schum., var. Himalayense. 

 Urtica parviflora, Eoxb. 



I have described the life-history of this remarkable and very com- 

 mon ^cidium elsewhere,* so it is only necessary here to state briefly its 

 characters. The parasite gives rise to remarkable hypertrophies of the 

 tissues of the host invaded, usually the leaves and petioles, though fre- 

 quently also the stems. When attacking the leaves, it has a special 

 proneness to invade the main veins ; and, by causing very great hyper- 

 trophy in them, gives rise to remarkable contortions. When it attacks 

 the stem, it usually produces well defined comparatively large tumours or 

 excrescences. The parasite is usually found in its fullest development 

 during July. The hypertrophy of the parts invaded is due mainly to 

 the increased size of the parenchyma cells, which are stored with nu- 

 tritive material, and, to a very subordinate extent, to mycelial invasion. 

 The mycelium penetrates some of the parenchyma cells forming haus- 

 toria of the branched type. 



The spermogonia measure about 0"178 m.m. in depth and breadth 

 with a tuft of paraphyses 68 /w, long. 



The gecidiospores are contained in a peridium of a single layer of 

 flattened polygonal cells measuring on an average 20 (jl in diameter. 

 The oecidiospores are given off in long rows from basidia arranged 

 very regularly on a level base. They are yellow round bodies with 

 finely granular contents and beset externally with minute deciduous 



* " Scientific Memoirs by Medical Officers of the Army of India," Part II. 

 Calcutta, 1887. 



