![Sample our Bioscience journals, sign in here to start your access, Latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5925/TOC-Subject-Sample-2021-Bioscience.jpg"})
SUMMARY
Ontogenetic studies were made of five species of Boletaceae: three exannulate species with glandular-dotted stipe of the Viscipelles of Boletus (genus Ixocomus of the Europeans)—B. placidus, B. granulatus and B. americanus; two species of Boletinus—B. spectabilis and B. pictus.
The development of Boletus placidus, B. granulatus and B. americanus is fundamentally the same. The hymenium first forms gymnocarpically upon the apex of the stipe; the hairy margin of the pileus gradually incurves to make contact with the stipe as hymenial development continues centrifugally; and the margin later pulls away without leaving any semblance of annular material on the stipe. These three species are therefore all pseudoangiocarpic in Kühner's sense. As far as is known, this is the first report of pseudoangiocarpy in exannulate Boleti.
The annulate Boletinus spectabilis develops similarly and is likewise pseudoangiocarpic.
Boletinus pictus, likewise annulate, probably develops in a manner entirely similar to B. spectabilis, and is probably pseudoangiocarpic, but this cannot be stated certainly because the very earliest stages of the carpophore were not available.