294 DR. A. B. WALKOM OlS" NUMMVLOSPEliMlJM [vol. Ixxvii, 



very far from complete, and we still lack a satisfactory explana- 

 tion of its structure. 



We have next to consider to which group of the Cycadofilicales 

 the seeds described above as Nummulosjyermum belong. The 

 vascular system is similar to that found in Cardiocarpus (a platy- 

 spermic seed belonging to the Cardiocarpales ^), and also in some 

 of the Trigonocarpales. Numimilospermum itself appears to be a 

 platyspermic type of seed ; it is distinguished from a number of 

 the Upper Palaeozoic Cardiocarpales (^Cyclospermum, jRhahdo- 

 spermum, Cycadinocarpus, and JMitrospermiitn) by the way in 

 which the two vascular strands are given of£ from the main 

 vascular strand entering the base of the seed before it reaches the 

 sclerotesta (see B. Sahni, Bibliography, No. 6, fig. 7). 



In the apparent possession of a large pollen-chamber, Nummulo- 

 spermum shows a feature which is one of the characteristics of the 

 Trigonocarpales. 



The anatomical features then, so far as they can be made out 

 with any degree of certainty, appear to favour the reference of 

 this genus to the Trigonocarpales. 



In conclusion, it is hoped that, as a result of this paper, renewed 

 interest maybe awakened in the possibility of proving or disproving 

 the intimate association of seeds with Glossopteris in other areas 

 where this widely-occurring genus is found. 



I have once more to express my gratitude to Mr. B. Dunstan, 

 F.Gr.S., Chief G-overnment Greologist of Queensland, at whose 

 suggestion I first undertook the study of the fossil floras of 

 Queensland, and whose broad view of his subject is responsible for 

 the comparatively large amount of palseontological v^^ork (palaeo- 

 zoology as well as palseobotan}") that has been carried out in 

 recent years on Queensland material. I have also to thank 

 Prof. A. C, Seward for reading the proofs of this paper, and I may 

 perhaps be permitted to express an appreciation of his kindly 

 interest in my work at the other end of the world, an interest 

 which has helj^ed me over many difficulties, particularly in the 

 earlier stages of my investigations. 



BiBLIOGEAPIIT. 



(1) E, A. jST. Arber. 1905. ' On the Sporangium -like Organs of Glosso- 



pteris Broivniana Brongn.' Q. J. G. S. vol. Ixi, pp. 324-38 & pis. xxx- 

 xxxi. 



(2) E. A. N. Arbeb. 1905. ' The Fossil Plants of the Glossopteris Flora.' 



Catal. Brit. Mus. 



(3) W. Carruthers. 1872. ' Notes on Fossil Plants from Queensland, 



Australia ' Q. J. Gr. S. vol. xxviii, pp. 350-56. 



(4) J. M. Coulter & C. J. Chamberlain. 1917. ' Morphology of Gymno- 



sperms.' Univ. of Chicago Press. 



^ Following Prof. A. C. Seward's (Bibliography, No. 7, pp. 307-308) sub- 

 division of Palaeozoic Gymnospermous seeds into Lagenostomales, Trigono- 

 carpales, and Cardiocarpales. 



