NO. 23 ON PSOMIOCARPA, A GEINUS OF FERNS — CHRIST 3 



The sporang-ia, which are smooth, globose, pedicellate, with 

 thick ring-s of at least 20 articulations, as well as the ovate, brown 

 spores, are perfectly alike in the three species. 



As to the shape of the fertile segments, the distinction between 

 "globose" and "elongate" is not absolute. For example, a single 

 specimen of Psomiocarpa apiifolia, collected in 1895 at San Ramon, 

 Mindanao, by Copeland (no, 1777), has a fertile frond the pinnules 

 of which are not globose, but elongate and confluent, very much as 

 in the American species. 



The presence of such a striking genus in Asia and America, 

 although surprising, is not without parallel. One need cite only 

 the case of Loxsoma of New Zealand and Loxsomopsis of Costa 

 Rica. 



The phylogenetic relations of Psomiocarpa tend toward Dryop- 

 teris and not Polybotrya. The latter seems to have rather more 

 affinity to Polystichum, an intermediate form being Polystichum 

 apiifoliuni C. Chr. (Dicksonia Sw.; syn. Nephrodiuni duale Donn.- 

 Smith), which shows the trailing rhizome and the contracted fertile 

 frond of Polybotrya, though it has also a reniform indusium. 



