;2''*'>' ///' Ann ricilll 1 irohx/lsf . N.iV.Mlll.MT. ISill 
mid to lliciii li;i\i' lu'cn inldcd iiiiiny species IrDlu Lower (';iiiiltri:tii 
lloi'i/.oils liy VMi'ioils ;nitli(il's ;in(l ('speciMlly of l:ite liy .Ml". ('. H. 
Wnlcutt until we now linve whiit seems to he a very formidaltle 
array of spe<'ies. Tliese are all elassecl toj^ethcr as the •Oleii- 
ellii> fauna . luit there appears to he room for a considerahle iiii- 
liroveiiu'iit on this <i'eneral elassilleation in the future, when the 
relations of the ditfert-nt iirouiis of strata shall l)e hetter iinder- 
stooil. 'l"o the writer it appears that tlier«' are indications of mon- 
th:m oiu- horizon of life in the asseml»la<ie of forms that have 
heen collectively desien;iteil the ()Ieiielhis Fauna. This ajjpears 
to me to lie indicated hy the fauna of Washineton county. X. Y.. 
the source' of Kmmoiis' types, and which has heeii recently 
.studied hy Mr. Walcott."'' 
Intil lately, and in fact until .NIr. W'alcott undertook this ex- 
}»loration. this fauna was so imperfectly known, that except as 
regards Oh inlhis (isii/t/iiii<f(s no use could he made of Emmons' 
<liscoveries for the exact coinparison of faunas. 
It is true that 3Ir. S. W . I'ord pronounced Atajis triUnriitns a 
("onocorvphe. hut without a ti;^ure and without kuowinii tlie 
.sense in which he used the name no deiinite advanta<ie came 
therefrom. Tiiis term ( 'onocorvphe had l»ecu so loosely used in 
Knuland and elst-wliere that it had lost its generic value when 
cursorily used. .Mr. W'alcott s H<>iires however enahle us t<» see 
that Atujis trill lit lit IIS is a true ('onocorvphe. 
In takiiie- up the most prominent eenera of this \\'ashin*>toii 
county area one )nay heuiii with 
( 'iniiirnnijilir trdiiiiiltil. t 
This species is of ('special interest as couihininir the head ()f a 
( 'oiiocoryplie with the ))yuidiiini of a Cteiiocephalus. It is not 
a ('ti'uocephaliis however, liecause the characters of the head 
shield should rei-eive the lirst consideration, and these make it 
a Coiiocoryphe. .Vs a ('oiiocoryiihe it shoiil.l lia\-e hiit fourteen 
to sixteen seuiuents in the thorax: the seventeenth scirment in 
this species will represent the lirst seiiinent of the pygidium of an 
*Fauiia of ilie Upper Tiu-onic of Emmons in Wasliniirtoii Co.. X. V. 
('. D. Walcott. Am. Jour. Sci. Vol. xxxrv. Sept., 1887. 
+Tlie author fully auroes with Mr. Walcott that it would not he wise 
now to attempt to restore the name Atojis for ('onocorvphe as it would 
ujiset the iionieiirlature of the latter jrenus, largely used for more than 
forty years. Atops was not defined so as to he recognIzal)le, either at 
tlie lirst, or for inaiiv vears afterward. 
