40 T'ransactions. 
the upper surface, pallid yellow. ^ Peridia immersed, the margins alone 
showing, 0-1-0-2 mm. diam., margins incurved, dentate, white. Spores 
polygonal, elliptical, or obovate, 25-37 x 18-24 mmm. ; epispore hyaline, 
densely and rather coarsely verruculose, 1 mmm. thick, cell-contents tinted 
yellow, granular. 
Host: Olearia macrodonta Baker. Оп leaves and petioles. Herb. 
No. 277. The track, Clinton Valley (Otago), E. H. Atkinson! 18 Jan., 
1920. (Type.) 
The host is endemic, and is abundant throughout. (Cheeseman, 1906, 
. 286. 
З This species is separated from Aecidium Oleariae McAlp. on account of 
the much larger spores. Moreover, the minute immersed peridia and 
distorting habit are distinctive features. 
2. Овкро Persoon. 
‘Pers., Neues. Мад. Bot. Roemer, vol. 1, p. 98, 1794. 
П. Uredosori without peridia, frequently surrounded by or mixed with 
paraphyses, erumpent, definite, pulverulent, bullate or pulvinate, usually 
surrounded by the ruptured epidermis, sometimes long covered. r 
spores borne singly on pedicels, never catenulate, globose, elliptical. or 
obovate; epispore hyaline or coloured, verrucose or more commonly echinu- 
late, seldom smooth; germ-pores 2 to several, scattered or equatorial, 
conspicuous or indistinct, sometimes papillate. Germinating by the pro- 
trusion of a germ-tube which penetrates the host-tissues through the 
stomata. 
Distribution : World-wide. А 
This form oceurs in the cycle of certain species belonging to the families 
Pucciniaceae (excluding Gymnosporangium), Cronartiaceae, Coleosporiaceae, 
and Melampsoraceae, and is in fact the commonest of all spore-forms 
oceurring in the Uredinales. 
The form-genus is characterized by the spores being borne singly on 
pedicels, not in chains, and by the fact that the sori are naked and not 
contained within peridia. 
Twelve form-species are recorded in this paper; of these, nine are 
endemic, and the remaining three indigenous. 
Key ro FogM-sPEOIES OF (веро. 
Hosts belonging to the family Gramineae. 
long. 
Spores over 30 mmm. 
Epispore thin, 1 mmm. .. a 1. U. Crinitue. 
Epispore thick, 2 mmm. or more .. 2. U. karetu. 
Spores under 30 mmm. long .. cs 3. U. toetoe. 
Hosts belonging to the family Cyperaceae. 4. U. Scirpi-nodosi. 
Hosts belonging to the family Lili 
pispore minutely and closely echinulate 5. U. Dianellae 
coarsely and sparsely nulate 6. U. Phormii 
H onging to the family Chenopodiaceae 7. U. Rhagodiae 
Hosts belonging to the family Umbe 8. U. inflata 
i the family Compositae 
Epispore thin, 2 mmm. and under. 
Epispore closely and finely echinulate hg OH. U. tupare. 
Epispore coarsely and moderately echinulate .. 12. U. wharanui. 
Epispore thick, 3-6 mmm. 
Spores over 40 mmm. long e Ks .. 9. U. Oleariae. 
Spores under 40 mmm. long vi i» .. 10. U. southlandicus. 
