XLVIl] 



HECISTOPTERIS— ANETIUM 



243 



HECISTOPTERIS J. Smith 

 H. piLinila (Spreng.) J. Smith, the only species, is a minute depauperate 

 Brazilian and West Indian epiphyte, which was originally included under 

 Gymnogravime: but it was re-established as the sole representative of 

 J. Smith's genus by Von Goebel (Fig. 743). The plant shows characters 

 which help towards the interpretation of the whole family. The roots are 

 long and bear frequent root-buds. The rhizome bears clathrate scales, and 

 contains a simple protostele as in Monogramnie, from which the leaf-traces 

 arise as simple strands (see Williams, I.e. Fig. 24). The leaf is exceptional in 



Fig. 743. Hecistoptcris piimila (Spr.) J. Sm. To the right is a figure 

 showing habit, natural size: to the left a leaf, and leaf-tip with sori, 

 enlarged. (After Hooker, from Christ.) 



being deeply cut from the margin, the dichotomous lobes (well provided with 

 long spicular cells) being served by veins which are themselves dichotomous. 

 No vein-fusions are found. Upon the veins the linear sori are borne super- 

 ficially. The fronds reach a fertile condition very early: for instance, a sorus 

 may be borne on a leaf which shows only its second dichotomy. The 

 sporangia are of the usual type.' The special interest of this Fern is that it 

 presents a juvenile form of sporophyte, with precocious fertility (see com- 

 parison below). 



Anetium (Kunze) Splitgerber 



A. citrifolium (L.) Splitgb. is again a monotypic epiphyte of the western 



tropics. It has a slender rhizome, which branches dichotomously, bearing 



clathrate scales, and alternate leaves. The leaves may be 9 inches long and 



2 inches broad, with reticulate venation, and free strands at the margin : 



16-2 



