In a former paper (Trans. N.Z. Inst., vol. 58, p. 241, 1927) I listed the species under Polyporus radiatus (Sow.) Fr. since collections forwarded to the late C.G.Lloyd and J.R.Weir were so named by them, despite the coloured spores. Since then many additional collections have come to hand; and as in all spores are definitely brown, it is evident that this feature is constant for the species. I have also been able to compare our collections with I. radiatus, I. cuticularis, I. rheades and I. ludovicianus. All possess a monomitic hyphal system, long ribbon-like thin-walled brown generative hyphae (which are without clamp connections), honeycomb basidial type and brown acuminate setae. Specimens of I. radiatus from England (Birmingham, collected by W.B.Grove, forwarded by E.M.Wakefield) and Sweden (Vaidsatra, collected by Seth Lundell, forwarded by J.Ax.Nannfeldt) differ from the New Zealand species in that the poorly developed cuticle is concolorous with the context, spores are hyaline, setae are scanty--a half dozen at most being seen in the field of the microscope in contrast with the scores seen in New Zealand collections. I. cuticularis (from Fagus sp., Kew Gardens, collected by E.M.Wakefield) is readily identified by the unusual cuticle, which is composed of a dense tomentnm of chestnut-brown dendroid compound setae, branches of which are hamate. Spores are brown and 5-7 x 4-5 µ. I. rheades (from Quercus spp., West Okoboji and Iowa City, U.S.A., forwarded by G.W.Martin) possesses a striaose surface and is without a cuticle; spores, though brown, are larger than those of our species (5-8 x 4.5-6 µ). I. ludovicianus (from Wauchope, New South Wales, forwarded by J.B.Cleland) was held by the late C.G.Lloyd to be a thin form of I. cuticularis. It differs from this last in being without a definite cuticle. It differs also from I. nothofagi in this feature, in larger pilei, different colour of context and pores, and differently shaped spores.

The New Zealand species would therefore appear to be undescribed. It is apparently confined to species of Nothofagus and may be recognised by the small dark pileus with (when old) almost black surface and abrupt margin, definite shining black cuticle, pores 2-5 per mm., ferruginous broadly elliptical spores and abundant ventricose setae.