﻿Vol. 6 1.] SPOKANGIUM-LIKE OEGANS OF GLOSSOPTEBJS, 331 



Sphenophyllum, as described by Prof. Zeiller. 1 They are somewhat 

 larger than the sporangia of Biscopteris, 2 but not so large as those 

 of Zygopteris. 3 



There is also a certain similarity in shape and structure with the 

 sporangia of Biscopteris Rallii, Zeill., and of Sphenophyllum cunei- 

 folium (Sternb.) ; although in both cases such sporangia exhibit 

 features which are not present in the specimens described here. 

 The shape of the cells of the outer limiting-layer is, however, an 

 especially- conspicuous character in common. An even closer com- 

 parison may be found in the microsporangia of recent Cycads, such 

 as Stangeria paradoxa, Th. Moore (compare, in PI. XXXI, fig. 4 

 with fig. 5 : the latter representing the Cycad-sporangium), which 

 are neither dissimilar in size, shape, nor mode of dehiscence, and on 

 the whole agree better with these new specimens than any other 

 type of sporangium with which I am acquainted. 



It has been pointed out that the wall of these sac-like organs 

 was probably more than one layer in thickness, so far as it is 

 possible to judge of such a character in cases in which the anato- 

 mical structure is not preserved. This feature is also common to 

 fossil sporangia, such as those of Zygopteris, and many others. 



Further, if these bodies are rightly interpreted as sporangia, then 

 the sporangium of Glossopteris was exannulate, and in this respect 

 resembled a very large proportion of Palaeozoic fern-like plants. 

 If an annulus had been present : or if these sac-like bodies had been 

 united into synangium-like groups ; or, again, if the anatomical 

 structure had been preserved, their morphological nature would have 

 been obvious. But the fact that no annulus is present does not 

 militate against the sporangial nature of these new specimens. In 

 addition to the Palaeozoic plants, some recent Ferns, the Marattiaceae 

 in part, are exannulate, and the microsporangia of recent Cycads, 

 which these bodies so closely resemble, are also probably without 

 a true annulus. 4 



We have a further confirmation of this view in the fact that 

 these sac-like bodies tend to open longitudinally, in a manner 

 somewhat closely similar to the microsporangia of such a Cycad 

 as Stangeria, or the sporangia of the recent fern Angiopteris. That 

 these sporangium-like bodies dehisced appears to be abundantly 

 evident from these specimens, and their manner of dehiscence 

 is not unlike that of many Palaeozoic fern-like plants. Thus, 

 there seems to be little doubt., in the face of the whole of this 

 evidence, that the probable nature of these sac-like bodies was 

 that of a sporangium. A sporangium, however, should contain 

 spores, but unfortunately I have so far failed to obtain any evidence 

 as to the contents of these sacs. It is quite possible that the 

 spores may have been very minute. Certainly, if they were as 

 small as the pollen-grains of Stangeria, we should be hardly able 



1 Zeiller (93) p. 21. 



2 Zeiller (99) p. 18 & text-figs. 3-4. 



3 Scott (00) p. 288. 



4 Lang (97) p. 431 & (00) p. 297 ; Treub (81) pi. Hi, fig. 2. 



