1883.] The Serpentine of Staten Island, New York. 1037 
diverging features, which, as they are well known, need not be 
repeated here. The whole course of development shows that the 
insects have been derived from a form like Peripatus, while the 
Crustacea have had an ancestor resembling the Nauplius of the 
Phyllopoda or the Copepoda. In both the iusects and the Crus- 
tacea we have in the larval and in the adult state a serially seg- 
mented body with appendages on the metameres, but this merely 
points to a common Annelidan ancestor, and with the exception 
of the Mollusca is a feature common to almost all animals above 
the Ccelenterata. The ecdysis which occurs in the Arthropoda 
is not to be regarded as indicating close relationship, but rather 
as an adaptive feature, resulting from the unyielding character of 
the hardened integument. In short, the only point not to be 
easily explained, if we regard the two groups as not nearly 
related, is the compound eye common to both, and which occurs 
nowhere else in the animal kingdom. Still we have only to con- 
sider the close resemblance of the eyes of the vertebrates and of 
the dibranchiate Cephalopoda to see how little weight one organ 
can have in classification. 
In the foregoing discussion, which is merely suggestive and by 
no means exhaustive, no attention has been paid to the Tardi- 
grada, Pycnogonids, Limulus and Linguatulina. It may be that 
they will have to be elevated to groups each equivalent to the 
insects and Crustacea, or, as has been argued, that they are 
branches from the Arachnida. We do not at present know enough 
concerning the embryology of these groups to settle these points, 
but the little which we do know, when considered in connection 
with our anatomical data, is sufficient to show that none of them 
belong to the Crustacean Phylum. 
i 
:0:— 
THE SERPENTINE OF STATEN ISLAND, NEW YORK? 
BY T. STERRY HUNT, LL.D., F.R.S. 
| HE serpentine of Staten island appears as a north and south. 
range of bold hills rising out of a plain of Mesozoic rocks 
On the west side are Triassic sandstones like those of the adja- 
cent mainland, including a belt of intrusive diabase, and on the 
fast the overlying and nearly horizontal Cretaceous marls, which 
are traced south and west into New Jersey. The only rocks be- 
1 Read at Minneapolis meeting of A. A. A. S., Aug. 21, 1883. 
