C.—GEOLOGY 57 
In the same volume of the Philosophical Transactions (1757) Emanuel 
da Costa described the occurrence of impressions of ‘ herbae capillares et 
affines, the gramineous and the reed tribes; but, however, among them 
many rare and beautiful impressions undoubtedly of vegetable origin, 
and impressed by plants hitherto unknown to botanists, are not un- 
——s 
frequently met with.’ He also recorded cones in the ironstone nodules 
of Coalbrookdale. Da Costa accepted Noah’s universal deluge, and, as 
evidence, cited the faults in mineral veins. ‘These, he stated, could not 
have been the result of partial floods, for, if so, they should contain local 
_ plants and animals, whereas the fossils were of organisms from ‘ the most 
remote climes from those, where they now lie buried.’ He instanced 
specimens of the Indian reeds—bamboos—from England, rhinoceros 
bones from the Hartz forest, horns of the moose-deer and elephant from 
England, and exotic shells from Harwich. Leibnitz, in 1706, thought 
that some of the fossil plants found in Germany resembled living types 
in India. ; 
The mystery underlying these observations was explained more naturally 
by Jussieu in 1718,1° although his ideas were not accepted. He was 
certainly one of the first to show that the floras of the Coal Measures 
and that of recent times were totally distinct, and that the supposed 
analogues of Coal Measure plants could only be found among tropical 
forms to-day. ‘To quote his own words: ‘ These plants are so different 
from those of Lyons, of the neighbouring provinces, and even of the whole 
of France, that they seem to belong to a new world . . . and what is 
still more curious these plants either no longer exist, or, if they do still 
live, they occur in such distant lands that we should not have known of 
them but for the discovery of these impressions.’ He considered their 
analogues, as has been stated, to occur in warmer regions in America and 
parts of India, and, since fossil shells were found along with them, he 
thought they had been floated to France by ocean currents from the south. 
Summing up in relation to the ideas current in his day, he says: ‘ It is 
‘not necessary therefore in explaining these fossil plants to have recourse _ 
to sports and tricks of nature, nor to palingenesis, as some recent authors 
think. . . . And when one attributes them to the Deluge one does not 
see with certainty the impressions of mature and fruiting plants deter- 
_ mining the month or season of the Deluge, since these plants came from 
warm countries where plants ripened before those in this country.’ 
Vallisneri also, in 1721, criticising Woodward’s hypothesis, advocated 
another, namely, that the earth had been originally completely covered 
‘with water, the land appearing as the water gradually subsided. Moro 
in 1740 tried to apply the theory of upheaval of the classical authors to 
Vallisneri’s observations. He really resuscitated Hooke’s earthquake 
hypothesis. Generelli in 1748, in defending Moro’s notions, stated that 
vegetable productions were found in different states of maturity, showing 
that they were embedded at different seasons, and he explained this 
by recurring volcanic outbursts. Other workers were collecting and 
describing specimens of fossils, plants, both impressions and petrifactions, 
10 Jussieu, Antoine de, Acad. Sciences, 1718. 
