Comparative skeletal meshwork of colonial bryozoans - two distinct types of lace-like colonial organisms recovered from Devonian strata in Canada. 插畫檔

This plate displays two distinct types of lace-like colonial organisms recovered from Devonian strata in Canada. The upper figures illustrate a fragment of a specimen characterized by an exceptionally fine, net-like framework, shown at both natural size and significantly enlarged. This magnified view reveals a dense grid of rectangular and oval fenestrules separated by delicate mineralized bars. The lower figures depict a different genus, featuring a more robust architecture with prominent vertical ridges and large, elongated oval openings. The magnified section of this second specimen highlights the presence of numerous smaller, circular pits or apertures interspersed between the main windows, which originally housed the individual living polyps. These intricate, stony skeletons served as complex filtration systems, allowing the marine colonies to efficiently capture nutrients while anchored to the ancient Paleozoic seafloor.