VOL 



..y/''] PKOCEEDINGS OF TJll<: NATIONAL MUSEUM. 1 1 1 



Btrongly su^j^cstivi' of Picti/ohi /<(sciohi liiiinoiii-.* that I have docnuHl 

 it sKlvisab'lc to assign it tlio iihove iiiimc. 



Ill No. IS we also iiav(; a phiiit \vlii(;h is in :ill |>i'ohaI)ility tlie snine 

 Ki)e('ies. 



Fronds dichotomons, rainuli narrowly linear, 1 to Ift""" wich' ;ind 

 not (jostate, aggregated in tufts. This is a v<Ty iinpcTfect spceiinen, 

 but 1 think tluu-e <'an Ix^ little <loubt ast() its identity witii the preced- 

 ing. 



Dictyotites maximus, Hjt. iiov. J'l. xi, Fi^. 11. 



No. -50 is a fragment of a plant so imperfectly rei)resenting iinpoilant 

 details of structure as to render its proper relationship <v\tremely 

 problematical. 



Fronds ri^gularly dichotomous, divisions linear, 2.75 to 3.5""" wide. 

 Divergences of members 55'=> to f>(P. Midrib none, margins regular. 



Fn this specimen there are no normal terminations of the liinuili, and 

 tlui state of the preservation is such as to render it im])ossil»h' to de- 

 determine if the plant was originally costate. At each bifurcation, a third 

 member is seen, l)ut from their relative |)()si< ions 1 iiin led to consider 

 them i)arts of anothiM- plant iiccidentally a-sso('iiit<'d. The plant is c<'r- 

 tainly either //«^i.s'cr/^rs or IHcttjotites, hnt wliich is <loul)tful. I will, 

 therefore, ref<!r it ])rovisionally to Dicti/otUc.s maximum as indicative of 

 its obviously large size. 



Psilophyton grandis. h|i. iiov. I'l. .\ii, I'ij;. Vlo; I'l. .\iii, l'i<;. V2li; i'l. \iv, Fij,^ 12c. 



The material comprised in >[os. 15, 2.S, and 32 is all oft he same char- 

 acrer and obviously fragments of i)lants cd" the same sjiecies. No. 15 

 shows on one side numerous fragments of narrow stems of the same 

 size and (;liara.ct(M- as in N(). .32. On eacli side of the main axis thereis 

 a row of compactly arranged acute s<;ale8 1""" broad at the base in a 

 verti(!al direction and 2"'"' long. Tlnn-e is also a circinate termination 

 of a branch, whi<-h measures ]<="' in diameter. The opposite, side oft lie 

 same slab shows two fragments of stems. These are 18'"' long and 

 1.5''" wide, each. They show a somewhat carbonized mass, but no well- 

 dotined snrfacii markings. The margins show well develoi»ed scales. 

 These are 2""" broad at the base— measured vertically— and are dis- 

 tant, from center to <'enter, 5""". They are all more or less broken off, 

 but a prolongation of their sides shows them to lniv<^ been lanceolate, 

 acute, slightly curved upward, and 5"'"' long. 



In No. 2S there are on one side of the slab fragments of branching 

 stems (>""" to 8""" wide, with lateral rows of (;losely arranged scales of 

 the same dimensions as in 32 and 15. None of tliese stems show^ well- 

 delined surface markings. 



On the oppositeside of the slab are dichotoniously branching stems of 

 all sizes, evidently parts of the same or of similar plants. Nearly all 



"Harvey: NoreiH Horcali Americana, i, 108, I'l. viii, 15. 



