175 



Pterophyllum Strahani. N.S. 



Frond imperfect ; largo, sub-alternate ; pinnules mode- 

 rately "broad, linear, sub-opposite, roundly truncate at extre- 

 mities, distant and horizontal towards middle and base ; 

 approximate almost confluent, and becoming highly angled 

 towards apex of frond ; each pinnule inserted by its whole 

 base ; bases confluent, curving, and broadening out into a 

 narrow wing against rachis, between the middle and inferior 

 pinnules ; sinus rounded between the lower distant pinnules. 

 The pinnules vary considerably in breadth, and some of them 

 (three in specimen described) are cleft from the middle to 

 the apex. Nerves, fine, parallel, dichotomous, about 8 to 16, 

 according to breadth of pinnule ; rachis thick grooved and 

 striated. Lower and middle pinnules from 65 to 80 milli- 

 metres long, and from 12 to 15 millimetres broad. 



Dark brown shales, Augusta-road, New Town, associated 

 with Salisburia, JBaiera, Tceniopteris, Cijclopteris, Sagenopteris, 

 Alethopteris, Thinnfeldia, Sphenopteris, Odontopteris, Zeugo- 

 phyllites, etc. 



This remarkable fossil plant approaches close to Ptero- 

 ptiyllum Morrisianum, Oldham, from Bindrabun, Rajmahal, 

 India, and suggests affinities with European plants of Liassic 

 age. The extraordinary association of genera in Austral- 

 asian rocks of Mesozoic age, however, makes it hazardous 

 as yet to fix the exact position of these Tasmanian beds from 

 the association of genera in the opposite hemisphere. Con- 

 siderations regarding the centres of origin, as indicated by 

 the first appearance of Glossopteris in Upper Pakeozoic of 

 Australasia, suggest much caution in any attempt to break 

 up our Mesozoic rocks into minor divisions corresponding 

 with the sub-division of European rocks of the same system. 



I have named this fossil plant in honour of His Excellency 

 Sir George Strahan, K.C.M.G., Governor of Tasmania. 



Pterophyllum Risdonensis. Nov. Sp. 



This is a species occurring very abundantly in shales asso- 

 ciated with Brock's coal seam at Compton. The fronds are 

 too imperfect to give a proper description, although the 

 fragments show that the species is larger and very distinct 

 from P. Strahani, from New Town. 



The leaflets are broad, linear, closely set, and inserted 

 upon rachis by their entire bases ; extremities truncate or 

 obtusely rounded ; nerves strong, parallel, not dichotomous, 

 about 6 in the breadth of each leaflet ; the nerves are thus 

 wider apart than in P. Strahani. 



