Almost simultaneously, or but shortly after the perfection of the spores of _Penicillium_, other and very similar patches appeared, distinguished by the naked eye more particularly by their dendritic form. This peculiarity seemed to result from the dwarfed habit of the third fungus, since the varnish, though cracked and raised, was not cast off, but remained in small angular fragments, giving to the spots their dendritic appearance, the dark spores of the fungus protruding through the fissures. This same mould was also found in many cases growing in the same spots amongst _Penicillium chartarum_, but whether from the same mycelium could not be determined. The distinguishing features of this fungus consist in an extensive mycelium of delicate threads, from which arise numerous erect branches, bearing at the apex dark brown opaque spores. Sometimes the branches were again shortly branched, but in the majority of instances were single. The septate spores had from two to four divisions, many of them divided again by cross septa in the longitudinal direction of the spore, so as to impart a muriform appearance. As far as the structure and appearance of the spores are concerned, they resembled those of _Sporidesmium polymorphum_, under which name specimens were at first published,[T] but this determination was not satisfactory. The mycelium and erect threads are much too highly developed for a good species of _Sporidesmium_, although the name of _Sporidesmium alternaria_ was afterwards adopted. In fresh specimens of this fungus, when seen _in situ_ by a half-inch objective, the spores appear to be moniliform, but if so, all attempts to see them so connected, when separated from the matrix, failed. On one occasion, a very immature condition was examined, containing simple beaded, hyaline bodies, attached to each other by a short neck. The same appearance of beaded spores, when seen _in situ_, was recognized by a mycological friend, to whom specimens were submitted for confirmation.[U]