742 ZOOLOGY. 
eight pairs of legs is distinctly seen on one side of two specimens 
of Asaphus gigas, in the same position upon the eight thoracic 
rings of the two specimens, and that position is strictly homologi- 
cal with the base of attachment of the limbs of Isopods. There 
is an impression for a ninth pair of legs on the inner surface of 
the posterior angle of the cheek. 
This discovery shows more fully than is generally admitted, that 
trilobites are a synthetic type. At the same time it shows that 
the tendency is towards the Isopods.—L. Acassiz. 
ANcON oR OTTER SHEEP.— Professor Huxley, in an article on 
the “Origin of Species” (Lay Sermons, pp. 254-298), makes men- 
tion of the otter sheep which originated on the farm of Seth 
Wright, near Charles River, Mass. 
They appear to have been noticed by David Humphreys, F.R.S., 
and a skeleton of one was sent to Sir Joseph Banks in 1813. 
Huxley says Humphreys found it difficult to obtain a specimen 
at that date, and further says he ‘believes that for many years no 
remnant” of the breed ‘has existed in the United States.” In 
this latter statement, quite fortunately, Prof. Huxley is mistaken. 
Otter sheep were raised till within a few years on the farm of 
Hon. William Hale of Barrington, N. H. Mr. Hale has now 
ceased to raise them? but his son, Hon. Thomas W. Hale, tells me 
that he saw a flock a few weeks since on the farm of Joshua R. 
Chesley of Barrington, N. H. He thinks that possibly they may 
be found in Chichester, N. H., as some were sold from the home 
flock a few years since to be taken to that town. Now here is a 
trail that some of our naturalists should follow out. If the otter 
sheep were of sufficient importance to science for Humphreys sixty 
years ago to go to great pains to procure a skeleton to send to 
England, and if they afford important data on the subject of the 
origin of species, as with Huxley they seem to do, itis time they 
were reexamined by competent authority, and skeletons secured 
for our own museums. - 
The Messrs. Hale have a fund of information respecting these 
sheep, for they raised them for a quarter of a century. They 
secured their flock as the original one of Green was obtained, by — 
selecting from the offspring of an otter ram and common straight- — 
legged sheep. This ram was purchased at Sligo, in Somersworth, 
. H. Connection could doubtless be made thence with the Seth 
