MACALISTER—ON THE MYOLOGY OF THE OTTER. iy, 
caught and made prey of the bats; on the first occasion, however, on 
which he shot one, he should not fail to dissect the bird, with that end 
in view. 
After which the following paper was read :— 
Nores on some Pornts 1n THE Myotoey oF THE OtrER. By ALEXANDER 
MacauistER, L.K.Q.C.P.,L. R.C.S. 1. 
TurovueH the kindness of Dr. Mapother, I have had the opportunity 
of dissecting a young Otter which died in the Zoological Gardens, 
Phoenix Park, and as I have noticed a few points in its anatomy which 
may be deserving of record, I have thought it worth bringing under 
the notice of the Natural History Society. 
The common otter has been dissected carefully by Meckel, Cuvier, 
Haughton, and others, and I have on a former occasion examined the 
anatomy of a larger individual, consequently it might be expected that 
nothing was to be made out in its anatomy; but I think that some of 
these points, which I wish to advert to, are new, or at least not gene- 
rally known. 
The first point worthy of note is the arrangement of the flexors 
and extensors in the digits of the manus and pes. 
The flexors of the former consist of a flexor digitorum sublimis, a 
flexor profundus, and flexor pollicis longus: of these, the first was 
larger than the second, and the second and third were united, but no 
other points worthy of note were found. 
The extensors of the fingers present us with a double series arising 
from a common musculo-tendinous origin at the external condyle. 
There were two muscles, the extensor digitorum communis and the 
extensor minimi digiti (or at least the muscle whose diminished repre~ 
sentative in man is known by that name): the former was inserted into 
the pollex, second and third digits, while the latter was extended to the 
second, third, fourth, and fifth digits, acting thus as a double or sup- 
plementary extensor. In the specimen examined by Professor Haugh- 
ton, it was inserted into the third, fourth, and fifth fingers; but there 
was a second muscle or indicator inserted into the index and middle 
digits. Professor Haughton does not record whether the attachment 
of the latter was humeral or anticubital: if the former, then I would 
suppose that in the specimen examined by him the secondary extensor 
series was differentiated completely into the two parts, while in my spe- 
cimen the two were completely blended in their origin. It is a point of 
very considerable interest to find so complete a second group of exten- 
sors, as in the bear the second extensor is attached to the third, fourth, 
and fifth fingers; in the kangaroo the same; in the rabbit to the three 
inner digits, and in the agouti to two inner toes. 
In homotypical anatomy the importance of this group is very great, 
for, as I have tried to show in another place, we have reason to believe 
that there are for the several phalanges of the fingers three separate ex- 
