258 Scientific Intelligence. 
genus, having the thoracic and abdominal segments ennai homies 
3d. Limulus, Miller, having a head composed of cephalic and o 
thoracic segments, followed by 5 coalesced thoracic somites hearing 
branchie, and o one ‘or more coalesced abdominal somites, to which is artic- 
ulated the telso 
From this I infer, that Mr. Woodward proposes to separate as a new 
genus under the name _eenieasten those species formerly referred to 
Bellinurus, in which the y segments are anchylosed together. If so, 
our _— oie would fall into the latter group, under the name 
ep 
"ite tion of ‘the Rocks of Illinois, from Worthen’s Geological ios 
oe vol. 1, p. vill. 
Feet. 
Post 
Drift, Loess, etc =o, Sil poe, boulders, etc........ 150 
Eocene period Z Clays and greenish ae 150 
CaRBONIFEROUS Syst 
Carboniferous near oal-measures and Millstone pit: ——Coal, shale, clay, 
limestones, cae amet and conglome . 1200 
Mountain 5 eg Subcarbon niferous j panies "tnels group——Limestone, 
sandstone and shale, 800 
St. Louis beds.--Limestone and shale, . ce S08 
Keokuk soup —Limestone an and shale Pr ha | 
Burlington group.--Coarse, subcrystalline limestone, .......-+. oor 200 
iealehook ¢ group.—Shales, limestone, sandstone, etc. ...+-.2ceeee++ 150 
Devonian System. 
Hamilton — Genesee division,—“ Black slate” and grayish shale,..... 100 
Hamilton beds.—-Dark grayish fetid and lighter, more pure limestones, 120 
Upper Hdderterg tog eCorniterens and Onondaga beds.--Gray, more or 
ody lim 25 
Oriskany potad ‘oriskany—uppe r bed.——Quartzose sandstone, .....,.- +++ 40 
Oriskany—lower seem 3, Or nese k group. Prom ni Bi siliceous, very 
cherty ansgziociain e, usually in thin layers, ........+++++* 200 
= Upper Siturian. 
Lower Helderberg period. Lower Helderberg group, (D. shaly limestone of 
Y N.Y. geologists)--More or less magnesian and argillaceous lime- 
_ _. Stone, in thin layers, including flinty moxjeethatih i ne wi eet 00 
Niagara period, Niagara group.—Magnesian and argillaceous limestones... 200 
Lower Sriurian, 
Cincinnati period. oup.—Limestones, shales and — ne,... 140 
Trenton Le ‘Galena aay Tienton beds.—Magnesian and more or less pure 
Potsdam or Primordial period. St. Peter’s division—Pure quartzose candst, 120 
Calciferous division.—Magnesian limestones and sandstones,.....+-+- seen. 
he publication of the Illinois Report, I observe Quenstedt it figures, 9 
eee “A = of his Handb. der Petref., under the nam a Comparer (0 : 
little Crustacean from the Coal-measures of Germany, almost certainly congeneri¢ 
with an imperfect specimen referred by us isionally, to our Paleocaris typus. 
. Il Rep., ii, pl. xxxn, fig. 5a.) If Jordan’ ‘er ovigtoal figure, —— of the type of 
Gam: yan epredeebiky Pi Pictet, and that gi so econ see 
y accurate, the typical gare so sete Palaces very dis- 
Gampsonyz. 
