42 H. W. MARETT TIMS. 
they deem this delicate Fish to be unclean, and hold it as an 
abomination to them),”’ according to the Mosaic law, which 
regards as such “ whatsoever hath no fins or scales in the 
waters”’ (Lev. xi, 12). Consequently he figures the scale 
in this fish, a figure which is highly creditable. Moreover, 
he noted the imbrication of the scales and the fact that they 
varied in size in different regions of the body. He makes 
the assumption that the scales may be taken as an index of 
the age of the fish, for he describes the appearances thus: 
they were principally “composed of a kind of globules or 
little balls ... lying in rows contiguous to each other” 
which ‘‘ produced the appearance of divers circles or rings on 
the face of the scale. And although I did not observe these 
scales to be exactly alike, yet the circles or rings seemed to 
me to be of the same number in all of them, whence I was 
led to conclude, that the scale had been every year augmented 
by the addition of one circle, and consequently that, as there 
were seven circles in this scale, this Kel was probably seven 
years old.” A similar thing to that which “is evident in 
trees” or “ shown in horns whence we gather that as many 
knots or rings as are found on the cow’s horn, so many years 
of age is the animal.” 
On the authority of Mandl, Leeuwenhoek is stated to have 
subsequently abandoned this view of the rings on the scales 
as affording an index of age. 
An examination of the scales was made by means of sections 
and the appearances as seen under the microscope are repre- 
sented. He concludes that a scale is formed in each year, 
each succeeding scale being somewhat larger than its prede- 
cessor aud “glued” to its under surface. From the descrip- 
tion given, one is led to the conclusion that Leeuwenhoek 
regarded the rings as the edges of succeeding scales, though 
he does not expressly state it. ‘I'his point is of great interest 
in comparison with Williamson’s work (20) on the ganoid 
scales in 1842. That this view was not accepted at the time 
is shown by his remark, that “this assertion of mine is how- 
ever violently contradicted, because many people think that 
