250 The American Geologist. Octobt-r, isoti 
(fork piece or radial) reminds one of a rugose coral. The 
young examples of stelliformis are more elongate and less 
. lobed than the larger specimens^ but cannot be confounded 
with C. whitei. 
Codaster grandis is a rare form and mimics the granato- 
crinoids in shape. Its narrow, elongate ambulacra confined to 
the summit, the numerous exposed hydrospire slits, thin test 
and linear ornamentation are characters by which this peculiar 
blastoid may be readily recognized. It comes from the very 
base of the Upper Burlington, associated with G. magnibasis. 
G. Stella and G. calycinus. 
Codaster? lasviculus comes from the same bed and is more 
abundant than its associates. It may be recognized by its 
obconical shape and short, broad sunken ambulacra. This 
blastoid seems to belong to a genus other than Codaster and 
presents characters that ally it with both Phaenoschisma and 
Cryptoschisma. 
Metablastus lineatus is rare at Louisiana, but apparently 
ranges through both Burlingtons. A natural cast from Upper 
Burlington chert, in the writer's collection, is a veritable giant, 
being much larger than M, wortheni of the Keokuk. Speci- 
mens from the Lower Burlington are much smaller. 
Owing to the close relationship between the Chouteau and 
Lower Burlington faunae, it might not be greatly out of place 
here to review the blastoids of the Missouri Chouteau. The 
earliest described species is Granatocrinus roemeri from the 
lower beds. It occurs not rarely in southwestern Missouri and 
even as far north as Providence. 
Its globose shape, strong granulo-linear ornamentation and 
flat base will readily distinguish this species. G. sampsoni is 
a synonym for G. roemeri. It, however, probably comes from 
the Upper Chouteau. There is not so much variation in the 
ornamentation of this species as in C. melo but there is a 
strong resemblance in outline among some of the varieties of 
these two species. Roemeri is, however, not congeneric with 
C. melo. 
Granatocrinus mutabilis comes from the top beds of the 
Chouteau near Bowling Green and Curry ville. It is a very 
changeable species, the young of which have strongly convex 
, bases, v\-hile the adult specimens have either flat or slighth' 
