94 MESSRS. NEWELL ARBER AND J. PARKIN ON 
The strobilus, which has a length of about 12 cm., consists of an elongated 
conical axis, bearing several series of bract-like structures below,-tbetween 
which is packed a copious ramentum. Above these bract-like organs, 
recognised in figs. 2 and 3 by their hairy surface, and attached to the axis 
in a hypogynous manner, is a structure known as the “ disc,".formed by the 
basal cohesion of 18-20 bipinnate fronds, the male sporophylls. In fig. 2, 
one of the latter is seen in the incurved condition, and the other, asiexpanded 
Restoration of а longitudinal section through the amphisporangiate strobilus of 
Bennettites (Cycadeoidea), About natural size. (After Wieland.) 
when fully mature. In fig.3 several of the microsporophylls are indicated in 
the unexpanded state. The bipinnate frond bears many, very reduced pinnules, 
each supporting two sessile synangia. The mierosporophyll is bent inwards in 
the young state, for about a third of its length, and the secondary rhachides 
are folded inwards in pairs, lying in the plane of the primary rhachis. 
At the apical portion of the strobilus, at a later stage when the 
