This study describes Homevaleia gouldii H. Nishida, Pigg, Kudo et Rigby gen. et sp. nov., an ovule-bearing glossopterid organ, based on a combination of recently collected permineralized specimens from the Late Permian Homevale Station locality in the Bowen Basin of Queensland, Australia, and on previously studied material from the 1977 Gould and Delevoryas study. Homevaleia, which resembles the compression-impression genus Dictyopteridium, is an inrolled megasporophyll with a distinct keel that bears numerous (over 70) stalked ovules on its adaxial surface. Ovules are small, oval, with an elaborate mesh-like structure that is developed from the outermost integumentary layers. Specimens interpreted as representing different developmental stages show there is an apparent interrelationship between megagametophyte development and the opening of the surrounding fertile structure for pollination. Together, new information provided by this material enables better understanding of glossopterid reproductive structure and its function in one distinctive form.

We describe details of anatomically preserved fossil glossopterid ovules from the Late Permian of Queensland, Australia, that contain several pollen tubes at various stages of releasing flagellated sperm. Each sperm is approximately 12.7 microm long and 13.9 microm wide, with a conspicuous spiral structure comprised of a series of dots that resemble the position of basal bodies of flagella aligned along the multilayered structure (MLS). This configuration is similar to the helically arranged flagella in the sperm of cycads, Ginkgo, and many pteridophytes. However, the motile gametes of Glossopteris are considerably smaller than those of Ginkgo and cycads, and more similar in size, number of basal bodies, and number of gyres in their helix to pteridophyte forms. Glossopteris thus shares the intermediate stage of motile male gamete formation and apparently that of haustorial pollen tubes with cycads and Ginkgo.

Background/Purpose Computer‐assisted tissue imaging and analytical techniques were used to clarify the histomorphological structure of hepatic connective tissue as a practical guide for surgeons. Methods Approximately 5000 histological slides were prepared from liver specimens of five autopsied patients. Three‐dimensional (3D) reconstruction was performed and subjected to computer imaging analysis. Scanning electron microscopy was also performed on the liver specimens. Results The 3D reconstructed images revealed the running form of the vasculature and the relationship between the hepatic lobule and connective tissue. The hepatic capsule or portal pedicle was consistently located at the periphery of the hepatic lobules. An artificial intelligence random forest approach clearly segmented hepatic cells, type I collagen (CF), type III collagen (RF), and other cells. The hepatic lobule, portal region, and hepatic capsule were significantly distinguished based on CF and RF occupancy. The capsule directly covering the liver lobule with an RF concentration up to 87% was provisionally named the proper hepatic capsule. The existence of a proper hepatic ligament with distinct occupation rates of CF and RF was also suggested. Conclusions The identified proper hepatic capsule and ligament can be important markers for demarcating the dissecting layer during surgical procedures.

Ediea homevalensis H. Nishida, Kudo, Pigg & Rigby gen. et sp. nov. is proposed for permineralized pollen-bearing structures from the Late Permian Homevale Station locality of the Bowen Basin, Queensland, Australia. The taxon represents unisexual fertile shoots bearing helically arranged leaves on a central axis. The more apical leaves are fertile microsporophylls bearing a pair of multi-branched stalks on their adaxial surfaces that each supports a cluster of terminally borne pollen sacs. Proximal to the fertile leaves there are several rows of sterile scale-like leaves. The pollen sacs (microsporangia) have thickened and dark, striate walls that are typical of the Arberiella type found in most pollen organs presumed to be of glossopterid affinity. An examination of pollen organs at several developmental stages, including those containing in situ pollen of the Protohaploxypinus type, provides the basis for a detailed analysis of these types of structures, which bear similarities to both compression/impression Eretmonia-type glossopterid microsporangiate organs and permineralized Eretmonia macloughlinii from Antarctica. These fossils demonstrate that at least some Late Permian pollen organs were simple microsporophyll-bearing shoot systems and not borne directly on Glossopteris leaves.

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