384 = J. D. Dana—Hornblendic and Augitie Rock. 
Ophiurans of many species were very abundant in numerous: 
localities. Among those of special interest are Ophiomusium. 
armigerum, abundant and large, in 17381 to 23869 eit . 
Ophioglypha convexa, in 1608 to 2574 fathoms: O. lepida?* 
taken in vast numbers at alanis 2221, in 1525 fe se Ae 
common in many other places, in 1168 to 2574 fathom 
A fine large new species of the genus Ophiochiton (0. grandis 
V.)+ was taken, both last year and this, in 888 to 1080 fathoms. 
This genus was not before known in this region. 
Art. XLVIL—WNote on the Cortlandt and Stony Point Horn- 
blendic and Augitic rock ; by JAMES D. Dana. 
IN my paper on the rocks of Westchester County, N. Xa I 
described certain massive hornblendic and augitic rocks, for the 
most part chrysolitic, from the town of Cortlandt and from 
ered with rather large, angular paxillz, those in the center becoming much 
smaller. The paxille bear close clusters of short, thick, obtuse or rounded 
than b cept ll 
small, flattened granules. The lower plates are similar to and opposite the upper 
ones, their upper half bearing granules which change to small sharp spinules 
down, a some specimens several longer spinules are developed on the 
central part of some of the plates h ral areas are sm see 
rather large plates, which bear small obtuse s oe a som larger one 
ua. cupyi n ; 
strongly inward with deep notches between hla Bach bears a ae group 
of six to eight slender spinules directed inward, while on the middle of the plate 
Sede is a group of eight to ten smaller, iat airsigabt spinules. Color. in life 
pale 
Gre aa radius of one ame largest specimens, 74™™; lesser radius, 18"™; 
breadth of arms in middle 
This species wa ; yipe in 2 wkd. 6 t stations 2041, 2042, 2043, in 1467 to 1608 
fathoms; and in t station 2174, in ots fathoms (No. 7963); and gous 
2226, in 2021 Sthiene (No. 8151), three specim 
his resembles O. lepida Lym., but the di ak i is sparcely covered with small 
ecdtae ~vantg it may be epee % var. spinulosa. 
+ Ophiochiton grandis V., sp A large species with the disk rounded, car- 
inated at the margin, its balace: covered h numerous unequal imbricated 
p : ma : - 
The 
the upper one longer than the fos tangy The tentacle-pores are large and each h 
large, round, flat The ventral arm-plates are broader than ae 
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flatter than the inner ones, which are conical and pobstg A sim miler adian papilla 
nds above the teeth. Color in alcohol dull yellowish brown. 
eae of disk, 30™"; breadth of arms at base, 4°5™™; length of longest 
arm-spin 
setees eae: 2211, in 924 to 1080 fathoms, 1884; station 2116, in 888 fathoms, 
1883 (No. 6624). 
