570 Benson.—Mazocarpon or the Structural Sigiliariostrobus . 
Manchester Collections. I also wish to gratefully acknowledge his loan of 
an excellent preparation from a Shore ball, from which Fig. i is pre¬ 
pared. 
In the spring of 1913, having exhausted my own supply of Shore balls 
in the search for more information of this structure, Prof. Oliver kindly 
allowed me to cut some of his supply. Almost immediately, by exceptional 
good fortune, a radial section of the megasporange (Fig. 5) was secured. 
This enabled me to correlate a number of other sections. Shortly after, 
from three successive balls, were added not only a series of five sections 
tangential to a megasporange but a similar series of four through a well- 
preserved, large microsporange. Microsporangia had not previously been - 
observed in the Upper Carboniferous rocks. 
Other objects, bearing on this research, found at the same time, will be 
referred to later. 1 
For the present it is sufficient to add that Dr. Scott, with whom I had 
hoped to co-operate in the description of the new form, most generously 
handed over to me his specimens of Mazocarpon , including a fine series of 
three longitudinal sections through a mature megasporangial cone from 
Hough Hill, and suggested that I should give a short account of the work 
at the Australian Meeting of the British Association in 1914. 2 For many 
other tokens of kind interest in the research ,1 owe Dr. Scott grateful 
acknowledgement. 
Section II. The Megasporange. 
The megasporange resembles in many respects that of Lepidostrobus. 
It is a bulky, radially extended body attached to a bract along its whole 
length. The wall is composed of a palisade and subjacent parenchyma. 
The sporogenous tissue is found lying over a well-developed subarche- 
sporial pad. 
The new characters are (1) the large amount of persistent, sterile tissue 
and its differentiation into various types, e. g. transfusion tissue, tapetal 
tissue, &c. 
(2) The prolongation of the wall into a shovel-shaped distal lamella 
which fits into the concave upper surface of the bract to which the sporange 
is attached. 
(3) The form and distribution of the spores and their limited number. 
It was owing to the persistent, sterile tissue, which by enveloping the 
dark-coloured spores gives the sporange much the appearance of a sausage- 
roll, that the name Mazocarpon (nafa = a loaf) was selected. 
A mass of transfusion tissue consisting of scalariform tracheides is 
clearly to be seen at the base of the pad in the Manchester slide 472 A 
1 See Part II of this paper. 
2 British Association Report, 1914, p. 584. 
