On dead wood, bark, and palm rachids, (1-10) Auckland Prov., (1-3) Brachyglottis repanda, (1,2) Cossey's Creek Dam, Hunua, 12.11.1963, PDD 20556 DAOM 109501), PDD 20555 (DAOM 93832); (3) Summit of Whitianga Road, Coromandel Peninsula (300m), 21.VII.1963, J.M.D., DAOM 109518; (4,5) Coprosma robusta. (4) Titirangi, 27.11,1963, J.M.D., DAOM ; 10213; (5) Cascade Kauri Park, Swanson. 8.1.1963, PDD 20404 (DAOM 109742); (6) Coprosma sp., Walker's Bush, Waitakere Range, 30.1.1963, DAOM 109343; (7) Freycinetia banksii, Summit of Whitianga Road, Coromandel Peninsula (300m), 21.VIII.1963, DAOM 93897; (8,9) Geniostoma ligustrifolium, (8) Home Track, Waitakere Range, 9.X.1963, J.M.D., PDD 21605 (DAOM 110231); (9) Rangemore Track, Waiatarua, Waitakere Range, 8.V.1963 ' J.M.D. and S.J.H., PDD 21060 (DAOM 110232); (10) Ripogonium scandens, Cossey's Creek Dam, Hunua. 12.11.1963, DAOM 109495; (11-13) Rhopalostylis sapida, (11) North Auckland, Puketi Forest, 20.VI.1963, DAOM 109763; (12-14) Auckland Prov., (12) Titirangi, 27.11.1963, PDD 20620 ( type) (DAOM 93842); (13) Summit of Whitianga Road, Coromandel Peninsula (300m), 21.VIII.1963, PDD 21371 (DAOM 110230); (14) unidentified host, Home Track, Upper Piha Valley, Waitakere Range, 9.X.1963, DAOM 96209.

Coloniae tenuiter effusae, atrae. Mycelium superficiale ex hyphis ramosis, hyalinis vel subhyalinis, 3.5-4.5um crassis compositum. Conidiophora ex hyphis repentibus lateraliter oriunda, erecta, recta vel flexuosa, septata, 90um minusve cylindrica, 4.7-7.2um crassa, m longa, simplicia vel 1-2 ramosa, hyalina vel subhyalina. Conidia singula ex apice conidiophori oriunda, blastica, primo tenue ellipsoidea dein ellipsoidea vel late ellipsoidea, muriformia (vulgo 17 transverse septata), brunnea vel atrobrunnea vel atra. 70-100 X 36-70um. Tunica externa conidii ex cellulis pillidioribus composita et rostro recurvato apicali hyalino ad 25µm long. praedita. Conidia secundaria plerumque unilateralia apicem et basim versus aggregata, sessilia vel breviter stipitata (aliquando bi-stipitata), ad 12(-18)um diam., multicellularia, brunnea vel atrobrunnea.

(Etymology: this species is named for Dr Bernard Boivin, who, for 25 years, has patiently corrected my Latin diagnoses). Conidium initials are hyaline and narrowly ellipsoidal, soon becoming transversely septate; 17 transverse septa are commonly produced followed by longitudinal septa to give the initial a muriform appearance. One series of longitudinal septa is regularly periclinal and this delimits an outer, single layer of cells which are 2-4.5um thick; this outer layer expands but nevertheless retains its identity as a hyaline layer as the conidium initial becomes wider and ellipsoidal to broadly ellipsoidal. As septation and expansion of the lower part of the initial proceeds the distal end of the initial remains more-or-less unmodified as a hyaline appendage composed of one or two rows of short cells bearing an apical, longer, hyaline cylindrical cell which is 9-15um long and 4.5-6um wide. Secondary conidia arise on the still-hyaline conidium initial from cells of the outer layer which may become pigmented before the rest of the conidium cells 'secondary conidia' develop brown walls soon after their formation. Unequal growth of the body of the conidium initial results in a slight curvature and finally causes the conidium to assume a position oblique to or almost it right angles to the conidiophore; a similar bending of the rostrate apex occurs. Pigmentation of the conidium cells occurs soon after or during the formation of the first few secondary conidia but that of the single outer layer of cells is much delayed so that a characteristic appearance of a dark brown muriform body surrounded by a hyaline layer of cells is obtained. Eventually the outer layer also turns brown. The ontogeny of the 'secondary conidia' is of interest. They develop, not from a simple blastic extension followed by dictyoseptation, but by the production of short hyphal lobes on an extension of one or less commonly of two cells of the outer layer; these hyphal lobes become adpressed to form a spherical structure whose outer will has the appearance of textura epidermoidea in surface view. This outer layer presumably encloses a central cell. but this could not be determined. Examination of the type collection of sporium africanum Pirozynski (in Deighto it & Pirozynski 1966) indicates that the secondary conidia develop in the same way as do those of X. boivinii Furthermore, the 'secondary conidia' of X. thaxteri display an outer layer with a similar pattern: I assume that their development in this species too is the same. Xenosporium boivinii differs from X. in several characters. In X. africanum hyphae and conidiophores are more robust and pigmented, conidium initials are pyriform to broadly ellipsoidal and they lack the terminal unmodified apex which persists is an appendage in X. boivinii Furthermore 'secondary conidia' in X. africanum develop at or near the apex of conidia, and rarely along its side. According to the description, X. shoranoorense Rao & Rao ( 1973) resembles X. africanum but the conidia are much smaller; the conidia have no terminal appendage.

Holotypus in foliis emortuis Rhopalostylidis sapidae, Nova Zelandia, Auckland Prov., Titirangi, 27.11.1963, S.J.H. et J. M. Dingley, PDD 20620 (DAOM 93842).