[26 
COMPARATIVE ANATOMY. 
terlaced with one another; and the interlacing is perform¬ 
ed by means of a vast number of fibres, or teeth, which 
the laminae shoot forth on each side , and which hook and 
grapple together. A friend of mine counted fifty of these 
fibres in one twentieth of an inch. These fibres are crook¬ 
ed; but curved after a different manner: for those which 
proceed from the thread on the side towards the extremity 
of the feather, are longer, more flexible, and bent down¬ 
ward; whereas those which proceed from the side towards 
the beginning, or quill-end of the feather, are shorter, firm¬ 
er, and turn upwards. The process then which takes 
place is as follows: When two laminae are pressed to¬ 
gether, so that these long fibres are forced far enough over 
the short ones, their crooked parts fall into the cavity made 
by the crooked parts of the others; just as the latch that is 
fastened to a door enters into the cavity of the catch fixed 
to the door-post, and there hooking itself, fastens the door; 
for it is properly in this manner, that one thread of a 
feather is fastened to the other. 
This admirable structure of the feather, which it is easy 
to see with the microscope, succeeds perfectly for the use 
to which nature has designed it; which use was, not only 
that the laminae might be united, but that when one thread 
or lamina has been separated from another by some exter¬ 
nal violence, it might be reclasped with sufficient facility 
and expedition.* 
In the ostrich, this apparatus of crotchets and fibres, of 
hooks and teeth, is wanting: and we see the consequence 
of the want. The filaments hang loose and separate from 
one another, forming only a kind of down; which consti¬ 
tution of the feathers, however it may fit them for the flow¬ 
ing honors of a lady’s head-dress, may be reckoned an 
imperfection in the bird, inasmuch as wings, composed of 
these feathers, although they may greatly assist it in run¬ 
ning, do not serve for flight. 
But under the present division of our subject, our busi¬ 
ness with feathers is, as they are the covering of the bird. 
And herein a singular circumstance occurs. In the small 
order of birds which winter with us, from a snipe down- 
laminae, and cause that adhesiveness observable between the several 
laminae of the vane. 
The bristles are not of the same form on each side of one lamina ; the 
lower tier, Tab. XXIII. fig. 6. form a simple and slight curve, while the 
upper, fig. 7. terminate with three or four little hooks, which serve to 
catch the simple corresponding bristle, fig. 6. of the next lamina. 
* The above account is taken from Memoirs for a Natural History of 
Animals, by the Royal Academy of Paris, published 1701, p. 209. 
