NORTH-EAST OF SCOTLAND MOLLUSCA 99 
for work connected with his chair, and of the 
rapidity and careful accuracy with which he was 
able to accomplish it, was the preparation and 
publication, within two years of his appointment, 
of his History of the Mollusca of the North-East of 
Scotland. That work includes, with full descrip¬ 
tions, upwards of 300 species, all of which, except 
one, had, he says, been carefully examined by 
himself, while he had gathered two-thirds of them 
with his own hands—about twenty being new to 
science. 
In the work of collecting he was aided by 
members of his own family, by students, and by 
friends resident in various parts of the adjoining 
districts, all of whom, inspired by him, were more 
than willing to contribute to his work any aid in 
their power. 
In his preface to that book he remarks :— 
“I present it” (the book) “with confidence to 
the public, because I am conscious of having pro¬ 
duced it with great care, and because I think it will 
be useful.” It was intended, he says, for his pupils 
and persons commencing the study of mollusca; 
and on that account, he adds, he had made the 
descriptions fuller than usual, as he was anxious 
to induce them to go beyond mere nomenclature, 
and to make themselves acquainted with the 
structure and relations of the objects described.” 
He further observes, with justifiable but modest 
pride and prophetic forecast, that it was the “ first 
zoological work that has emanated from the 
