374 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1911. 
The history of the Maltese family of Kelleia is often referred to 
as an example of mutative changes in the case of human beings, 
The father and mother of this family had the ordinary number of 
toes and fingers, but their eldest son possessed six fingers on each 
hand and six toes on each foot. This child, Gratio, subsequently 
married and had children, several of them having six fingers and 
toes. This malformation was absent in the following generation, 
but reappeared in the succeeding family; it then seemed to have 
died out. Another remarkable instance of this kind is that of the 
flock of Massachusetts Ancon sheep. The deformity which charac- 
terized these sheep, however, disappeared in the course of a few 
years, it is said in consequence of the introduction of the Merino 
sheep into the United States. In both these cases of the sudden 
development of monstrosities it can not be said that new species, 
but only varieties, had suddenly come into being. Our knowledge, 
however, concerning the evolution of the simpler into complex 
orders of plants, like that of animals, must to a large extent be 
guided by information we derive from the study of their fossil re- 
mains—a branch of science which has only been taken seriously in 
hand within the last few years.” Palaeobotanists of repute, such as 
MM. Barrois, Bertrand, and Cayeux, are of opinion that in the 
earliest sedimentary or pre-Cambrian formations they have obtained 
evidence of the existence of rudimentary animals and plants, in the 
shape of protophytes and protozoans.t. However this may be, we 
know that numerous species of diatoms, seaweeds, and fungi exist 
in a fossil state in the coal measures of England and other parts 
of the world, and that the structure of these beings resembled those 
now flourishing. The higher plants, however, on which these fungi 
fed ‘‘have changed profoundly since” the coal-measure epoch, 
‘stimulated by ever-changing surroundings.” ? All the plants 
which existed during the Carboniferous period have become extinct; 
they were flowerless and otherwise differed from those of the present 
day; but this difference was in outward form, or the grouping of 
their cells, rather than in the functions performed by their vascular, 
respiratory, and other structures. Thus we find in fossil plants of 
our coal measures a layer of chlorophyll bearing cells situated 
beneath their epidermis, indicating the existence of a starch-forming 
system, worked by energy derived from sunlight. In each succeed- 
ing geological period the main types of vegetation changed, and 
each succeeding change advanced a step toward the types of the 
existing flora.* It was not, however, until we arrive at the Creta- 
ceous epoch that the existence of fossil flowering plants appear. 
1 Annual Report of the Smithsonian Institution for the year 1903, p. 512. 
2 Ancient Plants, by M. C. Stopes, D. Sc., p. 165. 
3Tdem, p. 40. 
