ECHINODERMATA. 
649 
pair of ambulacra extend on both sides of an elongated plastron to the base 
of the snout-like prolongation, where they curve sharply upwards and follow 
close to the abactinal part of the tost, along a marked wedge-shaped ridge 
extending from the apical system into the rostrum, protecting the anus, to 
the apical system, situated almost at the summit of the nearly vertical ante- 
rior extremity ; the pair of anterior ambulacra take a similar course, but 
curve more regularly, and do not extend beyond the median lino towards the 
posterior end ; the odd ambulacrum is made up of two lines of pores far 
apart, situated in the deep anterior groove. The four large genital openings 
placed close together, with the madreporic body tolerably well defined in the 
centre, are situated at the origin of the anterior groove. The actinal system 
is elliptical, in the trend of the groove, very large, edges sharply defined, 
covered by very minute plates; no floscelle; no petaloid portion in the am- 
bulacra. This is a living representative of Infidaster of the Cretaceous 
period. But one specimen was taken, at a depth of 349 fathoms. 
Cassidulida. 
Neolampas rostellatus, gen. et sp. nov., A. Agassiz, 1. c. p. 271. Outline 
from above resembling Bchinolampas, but more elongated. Three large genital 
openings; left anterior one atrophied, placed closely together; madreporic 
body restricted to a narrow ridge separating them. Anal system large, ellip- 
tical, occupying the whole of the posterior truncated end, somewhat as in 
Bothriopygm^ the test being turned in like the finger of a glove, while the 
anus opens at the end of a long, slender tube, extending well beyond the 
outline of the test, starting from the upper part of the anal membrane, which 
is covered by small plates, gradually diminishing in size, and eventually 
firmly soldered together to form the basis of the anal tube. Test thin ; mouth 
placed near anterior extremity, having a well developed lloscelle and pro- 
minent bourrelets ; spines straight, very fine, resembling those of the Scu- 
tellidae. Only of an inch, but evidently adult. From 100 to 126 fathoms. 
Echinolampas carato^noides, sp. nov., A. Agassiz, 1. c. p. 269, 36 fathoms. 
Rhyncholampas. A. Agassiz (/. c. p. 270) forms this genus for the Cassidulus 
caribhccarum, Lam. 
Clypeastrid(2, 
Stolonoclypcus 7'avenelii, sp. nov., A. Agassiz, 1. c. p. 205, off Charleston 
Bar, Florida, in 34 fathoms. 
Onistulum, TYosche\,=AstnclypeHs, Verrill; C. gratulans, Troschel, = ^4. 
manii, Verrill. See Troschel, I c. p. 52. 
Encope emarginata^ Ag. As synonyms : E. valenciennesii, Ag. ; E. suhclausa, 
Ag. ; E. ohlongaj Ag. ; E. qumqueloba, Ag. ; E. griesbacim, B^val ; E. emar- 
ginata, Ltk. ; Moulinsia cassidtdma, Ag. (young 1). See Agassiz, I c. p. 267, 
Holothuroidea. 
Uroxia, g. n., A. Costa, /. c. p. 57. Corpus ovato-fusiforme, postorius 
abrupto attenuatum ; pcdicellis per lineas quimpie ambulacrales duplici scrio 
dispositis, nec non in areis interambiilacralibus sparsis. Tentacula oralia 
decern, crassa; octo nornialia, requalia, ramis frondosis ; duo brevissima 
abortiva. U. aurmitiaca, A. Costa, 1. c. p. 58, tav. 3. fig. 3. 
1869. [voL. VI.] 2 Y 
