The Ascocarps in Species of Penicillium

SUMMARY

A morphologic study of the reproductive structures involved in the ascomycetous phase of 12 species (17 strains) of Penicillium and of one related species has revealed a surprising diversity in ascogonia and antheridia, in types of ascocarps, in the disposition of the asci, and in ascospore markings. Two divergent lines appear, but there are species having some of the characters of each line. The ascocarpic initials of Penicillium Wortmanni and P. spiculisporum are barely differentiated segments of the vegetative hyphae. Those of P. bacillosporum and P. luteum are paired coiled organs. In P. stipitatum, described as a new species, the fusion of the ascogonium and anfheridium results in the formation of a hypha 100–150 μ long at the tip of which the ascocarp forms. The ascogonium of P. vermiculatum is a davate cell, reaching a length of 250 μ, around the base of which the antheridium coils. In P. egyptiacum, P. Ehrlichii, P. javanicum, P. Brefeldianum, and Carpenteles asperum, the young ascocarp arises from the innermost branches of a tree-like system of branches. Penicillium Gladioli represents the sterile Sclerotium forming species. Byssochlamys fulva has a short hyphal coil from which the asogenous hyphae arise, and through the intervention of croziers naked asci develop. In the first seven species the asci are in chains and in the next four they are on stalks. All species studied are homothallic.