196 J. Starhie Gardner — Mesozoic Angiosperms. 



parasitic Dicotyledons, to which Rafflesia belongs, while Newberry 

 appears to regard them as possible Composites. 1 



The branches of Williamsonia gigas, Carr., are stout, densely clothed, 

 with remarkably thick and short sheathing leaves, atnplexicaul, 

 loosely imbricated, dorsally keeled or convex, inferiorly canaliculate, 

 and with lanceolate, stiff, and even spinous apex. They are coriaceous, 

 smooth, with entire margins and parallel veins, united by a delicate 

 network of oblique veinlets only visible with a lens. Many of 

 these stems are terminated by more or less developed globose 

 involucres, composed of at least one whorl of converging linear 

 bracts, bent inwards so as to form a chamber, which is sometimes 

 empty, showing the basal scar from which the interior organ had 

 become detached. The largest of these involucres are formed of 

 several rows of bracts enveloping a peculiar gourd-shaped body or 

 axis invested with a dense covering of compressed long narrow cells, 

 which Saporta regards as an investing mass of filaments and anthers, 

 such as that covering the spadix of Typha. Prof. Williamson calls 

 this a cortical layer, but has inferred that it possibly bore antheridial 

 organs : Saporta adds that these fell away after the pollen was shed, 

 leaving the axis bare. Saporta asserts, and Williamson thinks it not 

 improbable, that this involucre represents the male oi'gan of the 

 plant. 



Associated with them are found verticils of incurved bracts united 

 at their bases into a cup-shaped organism, which Williamson on the 

 one hand is confident have never been found attached to any other, 

 but which Saporta maintains are sometimes present in the interior 

 moulds, in which condition all the English specimens are found, 

 adhering to the gourd-shaped axis which he says it surmounted. 

 The important collection of Mr. Yates is now in the Jardin des 

 Plantes, and I have not had the opportunity of examining it since I 

 became interested in the subject ; but on the other hand Professor 

 Williamson certainly possesses a specimen in which each bract is 

 furnished with a pair of oblong depressions, which are clearly not 

 accidental markings as Saporta would believe, and are obviously 

 adapted for bearing a pair of ovules. The remarkable thing is that 

 none of the other numerous specimens, so far as I know, in our 

 public museums show any such marks. Moreover, the gourd-shaped 

 axis is sometimes prolonged into a peculiar point which can be most 

 readily described as in shape like a light-house, and which finds no 

 place in Saporta's restoration. 2 



The rest of the description of Williamsonia is taken wholly from 



1 Dr. Newberry describes a number of helianthoid flowers wbicb be calls Palcean- 

 thus, from tbe Cretaceous Amboy Clays, whicb are tbree to four inches in diameter 

 and greatly resemble Williamsmiia. He remarks that tbougb " so mucb like flowers 

 of Compositse, we are not yet warranted in asserting that such is their character," Bull. 

 Torrey Botanical Club, vol. xiii. p. 37, 1886. 



2 The cup is described by Saporta and Marion, Evolution des Phanerog. vol. i. 

 p. 240, as a large cup or bell-shaped expansion with fringed or lobed margin, com- 

 posed of coriaceous and fibrous tissue, comparable to the spongy apex of the fleshy 

 spadix of Amorphophallus, and more remotely with the tuft of leaves crowning the 

 Pine -apple. 



