Dicotyledonous woods from the Upper Cretaceous of Southern IllinoiS. Five species of fossil dicotyledonous wood are described from an Upper Cretaceous (Maestrichtian; locality in Alexander County, IllinoiS. U.S. A.Paraquercimum cretaceum has structure similar to the Fagaceae (evergreen Oak‐Lithocarpus) and Casuarinaceae and represents the earliest known occurrence of this structural type (large solitary pores and uniseriate and large multiseriale rays).Paraphyltanthoxyhin illirioisense and Icacinoxylon alternipunctata are species of genera represented at other Cretaceous and Early Tertiary localities In large diameter trees.Parabombacaceoxylon magniporosum has large diameter pores and scalariform perforation plates, a combination of characters that is extremely rare in the extant flora.Paraapocynaceoxylon barghoorni has a combination of characters represented in extant Apocynaceae. These five species lack growth rings, have high vulnerability indices (mean vessel diameter divided by mean number of vessels per square millimeter, and a relatively high proportion of ray parenchyma. They lack specialized wood anatomical characters, and a compilation of vessel element lengths in these and other Cretaceous woods indicates that short vessel elements (a derived character) were less frequent in the Cretaceous than in extant dicotyledonous trees.

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A new taxon is described from the Upper Devonian, Oneonta formation in the northern Cats‐kills of New York. Triloboxylon gen. n. is represented by petrifactions showing two orders of branching. The main axis bears branches spirally and the latter bear the ultimate appendages spirally. Ultimate appendages branch dichotomously twice, in one plane. Primary xylem of the main axis and branches is three‐armed with mesarch protoxylem extending in a continuous band within each arm. Primary xylem of the ultimate appendage is terete and dichotomizes twice. Metaxylem elements are characterized by scalariform and circular‐bordered pitting on all walls. The cortex is composed entirely of isodiametrical parenchyma cells. Triloboxylon is compared with other genera with three‐lobed protosteles. Its possible affinity with the Aneurophytales is shown. The morphological nature of the “frond” of the Aneurophytales and the possibility that the group possesses the morphological equivalent of simple leaves are discussed.

A new genus of pleridosperms is described from the uppermost Devonian beds from Ballyheigue, Ireland. I.aceya hibernica May & Mat ten is represented by stems bearing spirally arranged fronds. The base of the frond is swollen and is about the same size as the stem. Pinnae are borne alternately and apparently in one plane on the rachis. The anatomy of the stem reveals a three‐fluted protostele. Secondary xylem consists of rays and trachcids and secondary phloem is present. The inner cortex contains probable secretory and/or sclerotic cells. The outer cortex is of the spargaimm‐type. Rachial trace formation is described. The U‐shaped xylem strand of the rachis lacks secondary tissue. Pinnae traces are V‐ to C‐shaped. A presumed adventitious root has a triarch protostele, a parenchymatous cortex and lacks a ‘sparganum’ outer zone. I.aceya is believed to be a member of the Lyginopleridaceae. The divisions of the sympodial protoxylem strand forming the rachial trace is compared among the Aneurophytales, Buteoxylonaceae, Calamopityaceae and Lyginopteridaceae and is shown to be similar.

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