u 



MISS NELLIE BANCEOFT ON SOME 



There are several examples of this type in block I., it bein^, according to Peistniantel 

 (5, p. 45), of frequent occurrence in the Rajmalial Hills. 



The venation of the Ttilophyllum pinnse is of an ordicary cycadean type, there being 

 no midrib (PI. 8. fig. 4 «). The nerves are parallel and apparently end blindly. 

 Dichotomies occur even in the upper parts of the pinnse. In both species the pinnae 

 are entire, subalternate and closely-set on the upper side of the terete rachis, which 

 thus appears almost entirely on the under side of the frond (PI. 8. fig. 18). In most 

 cases compression has been too great to allow of the subauriculate nature of the upper 

 basal angle being distinguished, though the example figured shows it well (PI. 8. fig. 5 ; 



cf. 4, Taf. 1, figs. 2 a & 3 «). 



The abundance of Ftilophyllum fronds, particularly P. cutchense, in block I., indicates 

 their possible connection with the stem represented {cf, Seward, 27, pp. 192-194, text- 

 figs. 30 A & 32, a reference to a similar stem with P. cutchense leaves attached). 

 There are, however, no indications of actual attachment in the material now under 

 coDsideration. 



DiCTYOZAMITES, Oldh. 



h 



4 



DiCTYOZAMITES FALCATUS (Morris) nob 



Block II. shows many fragments of detached fronds referable to the genus Dictyo- 

 zamites, Oldh. (PI. 9, fig. la; PL 8. fig. 6; ^. 8, pL 2. figs. 5 & 6; 9, pis. 3, 4, 5; 

 4, Taf. 4. figs. 7 & 8; Tafs. 5 & 6; 19, pi. 24. figs. 1 & 2, Dictyopteris falcata). 

 The pinnse are alternate, A^arying somewhat with regard to size, shape, and form of 

 apex, and are inserted by the middle only of the base, being sessile or slightly stalked. 

 The basal angles are apparently subauriculate. The pinnse are specially characterized 

 by their numerous veins radiating from the base, dichotomising and anastomosing to 

 form a reticulum, of which tlie central meshes are long and nearly parallel, while those 

 towards the apex and margin are shorter. Morris terms leaves with similar pinnse 

 JDictyopteris faleata, believing them to be of filicinean affinities, but Oldham (19, p. 39) 

 prefers to regard them as cycadean fronds. He accordingly substitutes the generic 

 name Dictyozamites, retaining Morris's species. Peistmantel (4, pp. 18 & 19), con- 

 sidering Dictyo zamites to be characteristic of the Pi^ajmahal Group and purely Indian, 

 distingLiishes the type as D. indicus, but recent discoveries of exactly similar fronds in 

 other parts of the world render it advisable to retain the former name Bictyozamites 

 falcatus (see 16, 28, 41, 42). 



Sections ofrachises andpinn(B. — In the majority of cases, the rachises in section show 

 no clear structure, though in some examples the vascular system is seen to be composed 

 of separate strands arranged in a double series in the form of a U (PI. 9. fig. 7 ; PI. 7. 

 fig. 13; cf. 34, pl. 62. fig. 1 ; pi. 63, fig. 1 ; and 37, p. 99, fig. 52), a disposition probably 

 derived by the depression of the adaxial members of an original circular or elliptical 

 system having the xylem directed inwards. Such a system is seen in the leaf-bases 

 surrounding the cycadean stem in block I. (PL 9. fig. 8 ; PI. 7. fi^s. 17 & 18 ; of 37> 



