THE FERNS OF NICARAGUA. 



I 4 7 



The latter is once-pinnate, the former has one of the basal 

 pinnae divided into two pinnules. (See Fig. 1.) Some of the 

 pinnae are short-stalked. 



Reported from Chontales by Fournier and Hemsley (ibid.). 



6. A. PLATYPHYLLUM Swartz. PL IX, FigS. 4, 5. 



Presl, Tent. Pter., p. 157, pi. vi, fig. 11 ; Kunze, Analec. Pterid., p. 31, pi. xx; 

 Hook., Sp. Fil., vol. 11, p. 3. 



A. seemanni Hook., Sp. Fil., vol. 11, p. 5, pi. lxxxi A; Eaton, Fil. Wr. et 

 Fend., p. 201 ; Hook, and Bak., Syn. Fil., p. 121 ; Hemsl., Biol. Cent. Am., 

 vol. in, p. 611. 



The specimens agree exactly with Hooker's figure and 

 description of A. seemanni, excepting that one of the fronds 

 has one of the lowest pinnae compound, with four pinnules, 

 all the others being simple as in Hooker's description. Under 

 his description of A. seemanni Hooker says: "Were the sterile 

 pinnules entire, I could almost consider it identical with A. 

 filatyfihyllum of Swartz and Kunze; but I am quite puzzled 



with Kunze's specimens of ' -platyphylhimj which are 



A. kaulfussh." Kunze evidently distributed some specimens 

 of A. kaulfiissii, a very distinct species, under the name A. 

 filatyphyllion. His description and figure, however, very 

 satisfactorily correspond with the Nicaraguan specimens, 

 excepting that the margin of the pinnae is more deeply serrate 

 in the latter. Kunze, in his figure, represents the margin as 

 very minutely serrulate, and in the text, speaking of the pinnae, 

 says: "Margine fertili integerrimo; sterili tenuissime cren- 

 ulato." The size of the serrations in the sterile pinnae is 

 somewhat variable, and constitutes a character so unsatisfac- 

 tory in this genus, that specific distinctions cannot be wholly 

 based upon it. For that reason A. ■platyfhylhim and A- 

 seemanni are united. 



Rare, found on a rocky bank of the San Juan River below 

 Castillo. Only four fronds were collected. One of these 

 measures (without the stipe) 13 inches in length, and its stipe 

 is 20 inches long. 



This species does not appear in any of the Nicaraguan lists. 



