184 Dr. Ma ton's and Mr. Rackett's 
An excellent Monographia of the Helix decollata was published 
by 
BRISSON, 
whose observations are illustrated by thirteen figures, and they 
relate to the structure of the animal as well as to the shape of the 
shell. 
DR. FORBES 
gives, in the Philosophical Transactions, an account (which, how- 
ever, is much too concise) of a Patella found at Bermuda. The 
figure, as it exhibits only the structure of the animal, makes but 
imperfect amends for the deficiency of description ; and though a 
short addition is made to the latter by Dr. Morton, the species 
is far from being defined. 
In 176*0, 
KNORR, 
a painter of Nuremberg, began the publication of a work enti- 
tled " Les DSlices des Yeux et de I'Esprit." He did not live to 
complete it himself; but the task was carried on by his execu- 
tors, who concluded it with a sixth part, published in 1773. This 
last part contains forty plates of shells ; each of the five former 
was limited to thirty. There are, in the whole, 978 figures, very 
slightly engraved, but well drawn and most elegantly painted. 
No order is observed ; and many subjects are repeated, on ac- 
count of slight variations in the colour and contour. The last ten 
plates present white shells on a dark-coloured ground. With the 
second part a systematical table is given ; but this is connected 
only with the plates preceding, and very nearly agrees with that 
adopted by Rumphius, of which, in the present improved state 
of science, the reader will be content to take only a transient 
notice. The descriptions of the plates relate chiefly to the figure 
and colour of the objects represented, containing but few remarks 
concerning 
