152 'JllC AllWric.av Gaoloahf. March, 1895 
forms of the Paradoxides are only a titlie of the length of tlic 
giants of this fauna that appeared at a later time; compare, 
also, the earliest Dicellocephali with the later ones; the ear- 
liest asaphoid forms with Megalaspis or Isotelus; compare 
also the gigantic Terataspis figured by Prof. J. M. C'larke* 
with the earliest representative of its type. ['Terataspis 
iiraiiills Hall, Tenth Annual Report of the State Geologist, 
Albany. N. Y., 181)0.)* 
(' li(( I'dclcr of the J're-Ca iithriax Had iola riaii fauna. 
In noting the chfiracter of the fauna of these pre-( 'ambrian 
radiolarians, Mr. Cayeux observes that he found two groups 
"(legions)" known elsewhere and at a later time in a fossil 
state, and that these two groups form a notable ])art of the 
existing fauna of radiolarians. 
Among the genera present, Cenosph;ei'a predominates over 
all others. It is a genus that exists at the present day, and 
more than thirty species dwell in the ocean at the present 
time: and at all depths to 8,000 fathoms. Haeckel has made 
the genus to play an important part in the phylogen_y of the 
radiolarians, making it the stock form of the sub-order Spine 
roidea. Notwithstanding its great antiquity it is far from 
being the simplest of the radiolarians, being superior to all 
those without a skeleton, or with imperfectly trellised skele- 
t(tn. • 
Alongside of ( "enosphjera arp other Sph;eroidea nu>re de- 
veloped, representing some of the principal families of this 
sub-order. Several forms of radiolarians referable to higher 
orders are found, including the turreted forms of the ('yrtoi- 
dea and other Nassellaria. These occupy a high place in the 
classitlcation of the radiolarians, have j)layed an important 
part in the Tertiary ages, and multiply in the modern ocean. 
One fact remarked upon by Mr. (,'ayeux is, that while these 
higher forms are present, they are comparatively scarce; but 
the spherical forms, and especiall^y (Jenosph;era, are so abun- 
dant as to form the principal bulk of the individuals observed. 
In brief, '"there co-existed in the pre-C'ambrian simple radi- 
*It will be seen lliat from this point of view Ihc objeclion taken by a 
(icrman writiT to tlic small size of llu' mcslics of a frasimcnt of Cyatho- 
sponiiiii I'ound l),\ the prcscMil, writer in a Laur(Mitian quart/.itc near St. 
.lolm. will ha\(' no weiulit. We are naturally to look for Ihe chvartini;' 
of oriianir forms as we trace tliem to the earlier deposits. 
