pecans 
E. Billings on the structure of the Blastoidea. 353 
which latter decomposes another part of the cyanid of potas- 
A glance at the following formulas will show the relation 
between these new bodies and several others already known : 
Trichlormethyl-sulphon-chlorid (C Cl,)S8O,Cl (Kolbe). 
Trichlormethyl-sulphon-bromid (C 01,)8O, Br. 
Trichlormethyl-sulphon-nitrid (CC1,)SO, (NO,). 
Trichlormethyl-sulphuric acid (CCl, )SO,O0H (Kolbe.) 
Trichlormethyl-sulphurous acid (C Cl,)S8O OH. 
Methylsulphurie acid (CH ,)80,0OH (Kolbe.) 
Methylsulphurous acid (CH ,)SO OH (Hobson.) 
New York, January, 1869, 
Arr. XX XII.—WNote on the structure of the Blastotden S DE 
E. Bruuines, F.G.S., Paleontologist Canada Geol. Survey. 
THE remains of the Blastoidea have as yet proved to be 
extremely rare in our Canadian rocks, only five small speci- 
been collected up to the present time. While studying these 
Paper, I find that we have now sufiicient data to establish the 
following points :— 
1. In the genus Nucleocrinus Conrad, there are sixteen aper- 
tures in the summit. Of these the large lateral aperture is both 
Mouth and vent. There is no opening in the center of the apex 
Where the mouth has hitherto been supposed to have its posi- 
on. The ten so-called “ovarial orifices” are respiratory aper- 
Between each two of these one of the ambulacral grooves 
enters to the interior through a small pore which is a true ova- 
Nan orifice. There are thus ten spiracles, five ovarian orifices 
and one buccal and anal orifice—in all sixteen. : 
2. In Pentremites there are also five ovarian pores, in the 
Same position. The mouth is not in the center, but in the 
larger of the five spiracles, 
3. Codaster has no ambulacral pores in the so-called “pseud- 
. fields.” The striated surfaces in the interradial 
areas are true Cystidean rhombs of the type of those of the 
rocy. ine 
