Geological Society. 223 



PROCEEDINGS OF LEARNED SOCIETIES. 



GEOLOGICAL SOCIETY. 



May 4th, 1921.— Mr. R. D. Oldham, F.R.S., 

 President, in the Chair. 



The following communications were read: — 



1. ' An Ottokaria-\\kQ Plant from South Africa.' By Hugh 

 Hamshaw Thomas, M.B.E., MA., F.G.S. 



The object of this note is to record the discovery in the Vereen- 

 iging Sandstones of the Transvaal of a fossil plant which bears 

 considerable resemblance to the rare genus Ottokaria. Only two 

 specimens of this type have hitherto been described — one from the 

 Lower Grondwana of India, the other from beds of similar age in 

 Brazil, and little or nothing is known about its nature or affinities. 

 The present specimen agrees with the known examples in general 

 size, and in having a more or less circular lamina (or head) seated 

 upon a stalk ; but it also possesses an additional featm-e in a thin 

 flattened structure projecting beyond the head. This feature has 

 been called the ' wing,' but its original nature is very problematical. 

 It may have been formed from a platyspermic seed projecting 

 from the head, the latter being a kind of cupule ; or it may have 

 been formed from a thin envelope originally enclosing the head. 



Ottokaria was probably a reproductive structure, and its associa- 

 tion with Glossopteris suggests a possible connexion with this 

 plant, the reproductive structures of which are practically un- 

 known. It is not considered necessary at present to make a new 

 genus for this specimen, and the name of Ottokaria lesJiei is 

 assigned to it, after its discoverer Mr. T. NT. Leslie, F.Gr.S. 



2. 'On NummuloBpermuyn, gen. nov., the probable Mega- 

 sporangium of Glossopteris.'' By A. B. Walkbm, D.Sc. 



The Author, after referring to the evidence hitherto adduced with 

 regard to the natm-e of the spore-bearing organs of Glossopteris, 

 describes some seeds associated with the fronds of Glossopteris at 

 certain localities in Queensland. He refers the seeds to a new 

 genus, and describes them under the name Xnmmidospermuin 

 boioenense. The seeds vary in length from 9 to 11 mm. and from 

 8 to 1 1 mm. in breadth ; they are oval or circular, probably platy- 

 spermic, and possess a wide sarcotesta and narrow^ sclerotesta. The 

 nucellus has a prominent beak projecting into a narrow micropyle. 

 The vascular system is also partlv described. Nummulospermum, 

 though closely associated with Glossopteris fronds, has not been 

 found in actual connexion with them. Similar, and in some cases 

 identical, seeds have been found in close association with Glosso- 

 pteris at other localities. 



Remarks are added on the scale-leaves of Glossopteris, and on 



