176 J. SMITH ON THE GENERA OF FERNS. " 



lei ; indusium plane ; fronds caspifose, simple, linear-lanceo- 

 late, coriaceous, smooth, mar ginaie, from 1 to ^feet in length hy 

 4 — 6 inches wide. 



Species. 1. N. vulgaris, J. Sm. (Asplenium Nidus, Linn.) 

 2. N. musffifolia, J. Stn. 3. N. Phyllitidis, {D. Don.) 4. A, 

 Grevillii, (Wall.) 5. N. stipitata, J. Sm. 



Illust. Hook. Gen. Fit. ined. 



Obs. The habit of the few species constituting this genus 

 naturally indicates them to be distinct as a genus from any of 

 the preceding genera, and they are readily recognised by the 

 apices of the venules being combined by a marginal vein ; 

 the only character that distinguishes this genus from at 

 least two species of Asplenium, which are nearly of the same 

 habit with Neotlopteris. There is a structure worthy of 

 notice as regards the axis of venation, and which is well ex- 

 emplified in Neotlopteris ; the midrib of which is large, pro- 

 minent, and triangular, the lower part being furnished with 

 two distinct vascular chords, imbedded in the cellular struc- 

 ture; higher up they unite, a section exhibiting the appear- 

 ance of the two letter c's, joined back to back thus oc, the 

 superior margin of each producing the veins which diverge 

 t,o their respective sides, and each fascicle parts into two or 

 three branches (forked), which forking takes place entirely 

 within the substance of the midrib; therefore in such cases, 

 veins are apt to be considered much more simple in their 

 parts than they truly are. 



72 Antigramma, Presl, J. Sm. 



(Asplenii sp. Authors. Camptosorus, TAnk. Presl) 

 Veins forked ; venules angularly anastomosing and reticu- 

 lated, the marginal veinlets free. Sporangia produced on 

 the proximate sides of the primary venules of each fascicle, 

 constituting unilateral linear sori, usually confluent in pairs. 

 Indusia linear, the free margins of each pair conniving. 

 Fronds simple, lanceolate, cordate, entire or sinuous, smooth. 

 Examp. 1. A. rhizophylla, (Lin?i. Camptosorus, Link.) 

 2. A. repanda, Presl. 3. A. Douglasii (Hook, et Grev.) 



