This very curious and elegant genus of ferns, bearing its deli- 

 cate pateriform sori on the margin of the leaf, was first separated 

 as a genus by Hooker, in Hooker &i Greville, Icon. Filicum, where 

 in tab. 154, D. Macrei is beautifully figured. Kaulfuss, in his 

 Enum. Filicum, p. 225, had previously arranged a proliferous De- 

 pairia with Dicksonia^ as Dicksonia prolifera^ but the fructifica- 

 tion differs too essentially from Dicksonia to permit this arrange- 

 ment. From Cihotium also, with which Presl has joined it, the 

 habit and fructification differ. Depairia of Hooker will therefore 

 probably remain a good genus. In the Species Filicum of Hooker 

 now in course of publication, he transfers the specific name pro- 

 lifer a to his D. Macrei^ which he calls a synonym, and states 

 that " Kaulfuss, who first described this handsome plant, observes 

 that its rachis ' is proliferous, w-liich is not apparent in my spe- 

 cimens.' " He also describes a new species, D. Maihewsii. 



It is evident, however, from the specimens now exhibited, that 

 D. Macrei and D. prolifcra are by no means synonyms. This 

 genus would then consist of 1, i). Macrei^ as described by Hooker ; 

 2, D. prolifera [Dicksonia prolifera of Kaulfuss] which may be 

 described. Frond bi ?-pinnate, rachis proliferous, not glabrous, 

 pinnai opposite, elongate, acuminate, deeply pinnatifid, quite 

 approximate, segments lanceolate acuminate, veins both simple 

 and forked, those at the base of the frond nearly all forked, sori 

 at the termination of the forked veins, usually on the uppermost, 

 but rarely on both veins. The whole outline and appearance 

 quite distinct from either of the other species. It seems proba- 

 ble that a microscopic examination of living specimens would 

 exhibit other striking distinctions between these three species, the 

 evidence of which, in dried specimens, is not sufficiently marked 

 to direct a mature judgment. Thus the sori appear more sessile 

 in D. prolifera than in D. Macrei. The rachis also of D. proli- 

 fera is now partially covered with sporules, so as to give it a 

 rufous appearance ; they could not, however, attach themselves 

 thus, if the rachis was like that of D. Macrei^ glabrous. 



3. D. Mathewsii as described by Hooker. Mr. T.'s specimen 

 of this species is from the mountain Punkohala Waioli. 



Dr. Cabot, in behalf of Dr. Storer, exhibited a drawing 

 of Trichiurus lepturus, taken from a specimen 40 inches 



