﻿Vol. 6 1.] SPOKANGIUM-LIKE ORGANS OF GLOSSOPTERIS. 335 



sporangia — if these retorfc-shaped bodies are really of this nature — 

 were possibly borne on the smaller scale-fronds, is a new one, and 

 does not in any way involve the larger fronds. It has this merit, 

 that definite organs, which in size, shape, and structure have been 

 shown to be not unlike the sporangia of certain recent and 

 Palaeozoic plants, and are also aggregated into sori, are described for 

 the first time. Although the final proof of the sporangial nature 

 of these organs — the recognition of spores — is wanting, the 

 resemblance is sufficiently striking to warrant the term 

 sporangiu m-1 ike organs. 



If, as is suggested here provisionally, it should eventually prove 

 that these bodies are true sporangia, then it would seem to be 

 impossible to regard Glossoptei*is as a Pern allied to any recent 

 family of the true Ferns. It may have belonged to some extinct 

 race of Ferns, but it must be borne in mind that, although this 

 plant has been regarded as a Fern by most of those who have 

 studied it in the past, this view has been based on the similarity of 

 habit and leaf- form, rather than on any real knowledge of the 

 fructification. While it is true that the fronds of Glossopteris agree 

 fairly closely with those of certain species of the recent ferns Dry- 

 moglossum, Acrostichum, Onoclea, and others, as Prof. Zeiller 1 and 

 Mr. Seward 2 have pointed out, they are quite unlike any recent family 

 of Ferns in the characters of their sporangia. Dimorphic ferns exist, 

 in which the fertile fronds are smaller than the sterile, and in 

 which the lamina is not markedly reduced, as for instance, among 

 others, Acrostichum villosum, Sw. :j But in the case of Glossopteris, 

 the sporangia, if such be the real nature of these sac-like bodies, 

 would seem to agree more closely with the microsporangia of a 

 Cycad than with the sporangia of any living fern. 



Or again, even if the sporangial nature of the organs described 

 here be admitted, it may be doubted whether our knowledge of the 

 affinities of Glossopteris is thereby much advanced. Such evidence 

 as there is would tend to remove the genus from proximity to 

 the recent Ferns, despite its fern-like habit, and it has yet to be 

 ascertained whether Glossopteris was an isosporous or a hetero- 

 sporous plant. In the latter event, these sac-like bodies are probably 

 microsporangia. At present, however, there is no means of solving 

 this problem. 



There is still a further possibility to be borne in mind. It has 

 been recently shown that some of the most fern-like of all the 

 fronds of the Coal-Measures did not belong to the true Ferns, but 

 to a race of seed-bearing plants, for which the name Pterido- 

 spermeae* has been recently suggested. Some of the British 

 Sphenopterids and Neuropterids 5 are of this nature. There is at 

 least the possibility that Glossopteris may eventually prove to be 

 a seed-plant, in which case the similarity of these sporangium-like 



1 Zeiller (96 1 ) p. 309. 2 Seward (97') p. 319. 



3 Hooker & Greville (31) pi. xcv. 



4 Oliver & Scott (04) p. 239. 5 Kidslon (04). 



