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THE IDENTITY AND SYSTEMATIC POSITIONOF CAMAROSPORIUM ABIETIS

WILSON & ANDERSON

By MALCOLM WILSON

From the Mycology Department, University of Edinburgh

WHEN Camarosporium Abietis was described as a new species by Wilson& Anderson (1924) it was not known that a similar fungus had beenrecorded in America. Steganosporium cenangioides had already beendescribed by Ellis and Rothrock (1885) on Abies balsamea, and by thekindness of Dr C. L. Shear a specimen of this fungus, collected byDearness in Ontario (Fungi Columbo No. 4783), has been sent forexamination.

In the American material the pycnidia are generally smaller, butin other respects the fungus agrees closely with that collected inScotland on Abies Lowiana and there appears to be no doubt that thetwo collections belong to the same species. Dr Shear also agrees withthis conclusion.

Meanwhile ]0rstad had discovered the same fungus in Norway inthe vicinity of Bergen in 1925 on A. nobilis and A. balsamea and nearTrondhjem in 1926 on A. pectinata and recorded it as Steganosporiumcenangioides (Jorstad, 1925 and in litt.). Dr ]0rstad informs me that hehas no doubt as to the identity of the Norwegian and Scottish fungiand, as a result of the examination of the specimens which he wasgood enough to send me, I am of the same opinion.

Petrak (1927) gave a very full description of S. cenangioides fromspecimens collected by Dearness (Fungi Columbo No. 4783) and thisaccount agrees very closely with that of Camarosporium Abietis. Hepoints out that on account of its structure the fungus cannot be placedin Steganosporium and transfers it to Myxocyclus Riess, as M. cenangioides(Ell. & Roth.) Pet., referring to its resemblance to M. polycystis (B. &Br.) V. Hahn.

Grove (1937) records the fungus from several localities in Britainand places it in the genus Camerographium Bubak (Bubak, 19I 6) asC. Abietis Grove; he gives no reference to Steganosporium cenangioidesEll. & Roth.

Grove has very considerably emended the genus CamerographiumBubak and has made the limits so elastic that many of the pycnidialfungi with muricate spores could be included in it. If, however, thegenus is restricted to Bubak's description, based on the type species

Camarosporium Abietis 207

C. Stephensii (B. & Br.) Bubak, there appears to be little or no reasonwhy Camerosporium Abietisshould be placed in it. According to Bubak,Camerographium does not possess true pycnidia and is characterized byflat, hysteriform fructifications opening by a longitudinal slit andcontaining clathrate-muriforrn spores. The striking features in Myxeo­cyclus eenangioides is the shape of the fructifications, which are hemi­spherical or sometimes shortly cylindrical, circular in transversesection, reaching a height of about 0'5 mm. and opening by theirregular disintegration of the wall at the apex. The spores when ripeare dark brown, surrounded by a mucous layer partially derived fromthe swelling of the sporophores and possess usually one, occasionallytwo vertical septa in some of the horizontal loculi; there are noparaphyses. M. eenangioides possesses a distinct hypostroma embeddedin the tissues of the host, made up of pale brown fibre-like hyphaewhile in Camerographium the fructifications are described as "mycelio­hyalino lateribus ornata". Clements and Shear (1931) place Camero­graphium in the Hyalodictyae while Myxocyclus and Camerosporium areplaced in the Phaeodictyae, the former genus being distinguishedfrom Camerosporium by its mucose spores.

Grove (1937) states that Camerographium Abietis has been recordedfrom Droitwich on Pieea Pinsapo (= Abies Pinsapo) and from Battle,Sussex, on Pieea (Rhodes). I am informed that the latter specimencannot be traced in the Rhodes collection either at Kew or atBirmingham. As this is the only record on Pieea it appears possiblethat the host was really Abiesas the fructifications are stated to occurespecially" on leaf scars" .

The synonymy and distribution of the species is as follows:Myxoryclus eenangioides (Ell. & Roth.) Petrak. (1927).Steganosporium eenangioides Ell. & Roth. (in Ellis & Everhart, 1885).Camerosporium Abietis Wilson & Anderson (1924).Camerographium Abietis Grove (1937).On Abies balsamea, Pennsylvania, U.S.A. (Ellis & Rothrock);

Ontario, Canada (Dearness); and Bergen, Norway (J0rstad).A. peetinata, Trondhjem, Norway (J0rstad).A. nobilis, Bergen, Norway (J0rstad).A. Lowiana, near Edinburgh (Wilson).A. Pinsapo, Droitwich (Grove).

I wish to express my thanks to the Director of the Royal BotanicGardens, Kew; Dr C. R. Shear of the Department of Agriculture,Washington, U.S.A.; Dr 1. ]0rstad, State Mycologist, Oslo, Norway,and Dr C. G. C. Chesters of the Botanical Department, University ofBirmingham for assistance in the preparation of this note.

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208 Transactions British Mycological Society

REFERENCES

BUBAK, F. (1916). "Systematische Untersuchungen einiger Fame bewohnendenPilze." Ber. dtsch. bot. Ges. XXXIV, 30S.

CLEMENTS, F. E. & SHEAR, C. L. (1931). The Genera ofthe Fungi. New York.ELLIS, J. B. & ROTHROCK. In ELLIS, J. B. & EVERHART, B. M. (188S). "New

species of fungi." ]. Mycol. I, 88.GROVE, W. B. (1937). BritishStem-andLeaf-Fungi(Coelomycetes), II, 107. Cambridge.J0RSTAD, I. (192S). "Norske skogsykdommer, I. Naletre-sykdommer bevirket av

Rustopper, Ascomyceter og Fungi Imperfecti." Medd. Norske Skogforsoksoesen,6 pp. 107, 169. ..

PETRAK, F. (1927)' "Mycologische Notizen. IX, S79. Uber Steganosporium cenangioidesEll. & Roth." Ann. mycol. XXV, 193 (304).

WILSON, M. & ANDERSON, R. B. (1924). "Observations on Camarosporium Abietisn.sp." Trans. Brit. mycol. Soc. IX, 144.

(Accepted for publication I I May 1939)