or THE EOSSIL PLANTS OF THE COAL-MEASUEES. 
257 
chymatous form. Thick at the base of the seed, it becomes thinner as it rapidly con- 
tracts in size to form the prolonged micropyle, d, which is obviously curtailed of much 
of its normal length. At the chalaza (i) the cells of the membrane curve away on either 
hand, in lines which bend, first, downwards, then upwards and outwards from its junction 
with the endotesta, b. This latter membrane is again seen to be thin, and composed ot 
a single layer of delicate prosenchymatous cells, excepting at the chalaza (i), where they 
appear to be parenchymatous ; but it is possible that, at this point, the section may not 
be exactly central, and that, consequently, the cells may be intersected across their 
narrow diameters. At the opposite extremity the endotesta is prolonged [V) through and 
beyond the micropylar extension of the exotesta ; but the tissues of this region have 
obviously been injured. The nucleus and perispermic membrane are again wanting in 
this example. All the three specimens here described are from the Oldham nodules. 
The application of correct specific names to these Cardiocarpons is not easy. Mr. 
Carruthers, to whom I showed the original of fig. 116, considers it to be identical with 
his C. anomalum *. Though far from certain, not having seen Mr. Carruther’s speci- 
men, the seed which I have described may remain under that name, upon the authority 
of its author. 
I have found in the Oldham nodules several specimens of a small compressed Cardio- 
carjpon, in addition to a portion of one obtained by Mr. Butterworth. Their outlines 
were not very clearly defined, especially at the micropylar extremity ; but fig. 121 repre- 
sents the general aspect of most of the specimens, allowance being made for some 
uncertainty respecting the external contour of the apex. There is in all a smooth, 
flattened nucleus, with an investing layer, a, which extends considerably beyond the 
nucleus nearly all round the seed, but which is especially somewhat prolonged at the 
apex. In Mr. Butterworth’s fragment there is a slight longitudinal groove running 
down the centre of the surface of the nucleus, as represented in fig. 121. 
Fig. 122 represents one of a number of seeds on a piece of shale from the Newcastle 
Coal-field, and which I presume is the Cardiocarpmn acutum of Bindley and Hutton. 
It is possible that this may be the same species as fig. 121, in which case both may 
probably be identical with the C. Lindleyi of Carruthers f. But if so, the bifid extre- 
mity of the fruit in Mr. Carrutiiers’s plant, and in my fig. 122, has probably been the 
result of pressure, which has split open the patulous extremity of the micropyle. 
Fig. 123 represents a central vertical section of the upper half of a seed made in the 
plane of fig. 121. We here only see an exotesta, a , enclosing a large internal cavity; 
its upper extremity contracts gradually into a short and narrow micropyle, d, but which 
terminates in a trumpet-shaped mouth or exostoma at d'. We have shrivelled portions 
of an internal membrane at g, but I cannot ascertain what it is. Fig. 124 represents 
a transverse section of the same seed made a little below the base-line of fig. 123. We 
here see the lenticular form of the cavity enclosed by the testa, a ; and though the latter 
* ‘ Notes on some Fossil Plants ’ &c., fig. 3. 
t Loc. cit. fig. 182. 
