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Page number:14 
Remarks (public):Saccardo (1882) separated D. leptosporum from D. dendroides as a subspecies on the basis of its conidial characteristics, as he observed them in the type specimen: "conidiis paulo angustioribus, nempe 22 x 8, oblongis, 3-septatis, basi apiculatis, hyalinis". The type collection was obtained from dead wood in Newfield, New Jersey, by J. B. Ellis 3575. ApparentIy, D. leptosporum has been collected only in North America, and it is not so well known as D. dendroides. The first known collection from Mississippi was found at Catfish Point, August 2, 1960, overgrowing the hymenium of a Tomentella on bark at the base of a living box elder (Acer negundo L.), collected by P. L. Lentz, F.P. 110463. A specimen from Canada, ex Univ. Toronto Crypt. Herb., TRTC 32281, previously determined as D. dendroides, probably is an additional collection of D. leptosporum, although the conidiiferous apices of the Canadian specimen seem different from those of the collection from Mississippi in one detail.
The conidia of the specimen from Mississippi apparently are formed singly as blown-out bubbles at the apices of the conidiiferous branches (Fig. 6C). Development of the bubble-like young conidium is external to the progenitory apex of the branch, rather than phialide-like. A few conidia may remain in clusters at the ends of some of the branches for a while, thus seeming to indicate that several conidia may be produced in succession from the apex of a single branch. When this happens, no apparent structural alteration of the branch apex seems to result from the multiple-production process. During the formation of a conidium, the conidial attachment peg may be formed directly in line with the long axis of the conidium, and the entire conidium thus is positioned directly in line with the long axis of the conidium-bearing branch. However, the attachment peg of the conidium may be relegated to an abaxial position, in which instance the conidium deviates obliquely from the axis Iine of the conidiiferous branch.
In the Canadian specimen, overgrowing basidiocarps of Corticium radiosum FR. and Peniophora subulata Bourd. & Galz., the fertile conidiiferous branch tip apparently may grow beyond each successive Ievel at which a conidium has been produced. This results in the geniculate development commonly observed when successively produced apical spores are subsequently relegated to lateral positions (Fig. 6D). The conidia of the Canadian specimen seem slightly larger (and the small masses of spores somewhat more conspicuous) than those of the collection from Mississippi. However, this specimen from Canada much more nearly resembles the collection of D, leptosporum from Mississippi than it does D. dendroides, as represented by D. Saccardo's Mycotheca italica 1198.
Description type:Non-original description 
Description:Dactylium leptosporum (SAcc.) Lentz, stat. nov.; D. dendroides [Bull.] Fr. subsp. D. leptosporum Sacc. in Michelia 2: 576, 1882.
Conidial fructifications (Fig. 1B) consisting of scanty, delicate, puberulentIy mucedinous white wefts of conidiophores.
Conidiophores (Fig. 6A) characteristically verticillate, with branches developing in whorls of three or four, in pairs, and singly, bearing conidia apically or producing secondary whorls of conidia-bearing branches.
Conidia (Fig. 6B) long-ellipsoidal or cylindrical, each bearing a peglike apiculus and rounded at the apex, smooth, 3-septate when mature, not constricted at the septa, thin walled, colorless, 22-27 x 7.5-8 (-10) µm.
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