248 
PEOFESSOE W. C. WILLIAMSON ON THE OEGANIZATION 
that between the ‘parenchymatous cells within the exostome and the prosenchyma of 
the nucular membrane, of which latter, however, the former may possibly be merely a 
prolongation. 
Whilst I believe that I have correctly interpreted the homologies of the nucular region 
of this distinct seed, difficulties present themselves in reference to the micropylar extre- 
mity. It is evident that there was a very wide micropyle, so far as the sarcotesta is 
concerned, reminding us of what we see in the young states of Juniper us, Taxus, 
Callitris, and some species of Pinus ; but we see, from fig. 94, that this cavity was 
nearly filled up with the cellular parenchyma ( h ). Is this latter tissue in any way the 
representative of that seen in the lagenostome of several of the species previously 
described in this memoir'? If not, did the pollen-grains pass down the open space 
between it and the canal in the sarcotesta, or did they descend to reach the nucleus 
through the canal passing through the centre of the parenchyma? At present no 
satisfactory answer can be given to these questions, and I only propose them to indicate 
points awaiting further investigation, but for which we must await the discovery of addi- 
tional specimens This seed is from the Oldham nodules. Its maximum length, 
exclusive of the funiculus, is ’25. 
The next seed to be examined is the Trigonocarpon* olivceforme , which was long ago 
made the subject of the memoir by Dr. Hooker and Mr. Binney already referred to, 
published in the ‘ Philosophical Transactions,’ vol. 145. These seeds are found in 
great abundance in a quarry of sandstone belonging to the Upper Coal-measures, known 
as the Peel Delph, near Worsley, in Lancashire. The chief accumulation of them in 
that quarry is in a very thin seam, in which they are clustered together in the greatest 
profusion, having evidently been drifted from some locality where the trees producing 
them overhung the water, and into which they had been shaken, when ripe, by some 
violent primaeval tempest, and then drifted upon a neighbouring sand-beach. Other 
drifted plants of the Coal-measures are frequently met with in the same locality. These 
seeds are very rare in the calcareous nodules of the various localities near Oldham. 
Mr. Binney met with great numbers of them in a deposit at some other place in 
Lancashire, but of which he has not recorded the name, beyond saying that they were 
from one of the Ganister coals of the Lower Coal-measures. 
My two valuable auxiliaries, Mr. J. Butterworth and Mr. Nield, have met with but 
very few specimens of these seeds in the Oldham deposits, which belong to the same 
geological horizon as that from which Mr. Binney obtained his examples. Some of 
these specimens my two friends have kindly placed in my hands f. 
* There is much confusion in the spelling of this generic term. In his original ‘ Prodrome ’ Brongniart 
adopted “ Trigonocarpum.” In his later ‘ Tableau’ he changed it to “ Trigonocarpon ; ’ whilst in his yet later 
memoir on the St.-Etienne seeds he again alters it to “ Trigonocarpus.” Hooker and Binney adopted “ Tri- 
gonocarpon Dr. Dawson writes “ Trigonocarpum and Professor Newberry “ Trigonocarpon.” 
t Being anxious to make this renewed study of Trigonocarpon as searching as possible, I placed two of these 
specimens in the hands of Mr. Cutteee, the well-known lapidary, with instructions to obtain for me as many 
