6 66 Campbell. — -The Structure and Affinities of 
intermediate between that of Angiopteris and the other Marattiaceae in 
having the early leaf-traces remain separate longer than is the case in 
Angiopteris. 
The adult sporophyte is like Danaea and Archangiopteris in the 
simply pinnate leaves. The sorus is made up of separate sporangia as in 
Angiopteris, but the sporangia are much more crowded and very much more 
numerous, and in this latter respect it is most like Archangiopteris. The 
number of sporangia in the sorus of Angiopteris usually ranges from about 
7 to 15; the maximum number seen by the writer was about 25 in 
A. Brooksii , Copeland. In Macroglossum Alidae the maximum exceeded 
70; in Archangiopteris , according to Christ and Giesenhagen, it may reach 
120. The sporangia themselves, to judge from the figures of Archangi- 
opteris, are more like the latter than they are like Angiopteris. From the 
latter they differ markedly in shape, and in the much less developed annulus. 
The difference in shape is correlated with the sinking of the sorus between 
the ridges and by the greater crowding. The indusial hairs are much 
better developed in Macroglossum, and also are much more like those of 
Archangiopteris than Angiopteris. In the latter, the conspicuous ridges 
between the sori are quite wanting and the sporangia stand quite free above 
the leaf ; the sori are usually separated from each other by a considerable 
interval. A section of the leaf in Angiopteris shows no trace of the large 
mucilage ducts found in Macroglossum, and the palisade tissue is not so 
well marked, although it is well developed in some species. 
While it is evident that Macroglossum should be included in the 
Angiopterideae, its affinities seem to be with Archangiopteris rather than 
with Angiopteris. The resemblances to Danaea are interesting, but it is 
doubtful whether they indicate anything more than analogies. It is of 
course possible that the elongate sorus with its individual sporangia may 
have been derived from the solid synangium of such a form as Danaea, but 
there is no positive evidence that such has been the case. 
Of the two species examined, M. Smithii, the plant growing at 
Buitenzorg, is more like Angiopteris than is M. Alidae. The sori are less 
elongated, and the small ones are not very unlike those of Angiopteris. 
Moreover, the sporangia themselves have the annulus somewhat better 
developed than is the case in M. Alidae. However, the differences between 
this species and M. Alidae are not very marked, and it is evident that the 
two are closely related, although probably specifically distinct. 
Summary. 
1. The genus Macroglossum comprises two known species, M. Alidae , 
Copeland, first collected at Bau in Sarawak, Borneo, and afterwards at 
Mount Penrissen, Sarawak ; M. Smithii ( Angiopteris Smithii, Raciborski), 
