MAini.wi) <;i:()i,()(ii< \i, siunkv 115 



Xcvfrdiclcss, tlic -I iiicliuc ;iiiil li)|)(i;^r:ii)liy (jI' those minute ami ap- 

 jiiiiciitlv iiisiLiiiilicaiil liddics Imvc liccii iiiv('sti<rate(l with great eare, and 

 a ])recis(' ikhiicikIjiI me otnlilislicd. l-'oi- the (lepression exteiidiii;,'^ from 

 the .'iiiliTinr iiijirLiin liackwn rd in ;i lidi-i/diitid dircclinii mi tin- ll;it or 

 (■(iii(:i\t' inner side. Koken lias proposed the (h'signalion ol' sulcus arusti- 

 /■iis. and this he I'e^iai'ds as I'liniisliin^f the most important (liagnostic 

 charaetci's. The scniptiii'c of the inner and onler .-ides, and nature of 

 tiu' pei'ipheral horder, whether .-hai'p or thiekene(l, <niooth. I'oldeil. (h'u- 

 titidated or incised, and \ai'ioiis niinoi' eharaetei's of like nature are all 

 taken into aceount in the attempt to identify detached specimens. 

 Their size, too, is held to l)e an iinpoi'tant distinguishing character. 



The most ])ainstaking' invest i,i;at ions on fossil otolites from hoth our 

 own and Eui-opean Tertiaries are those of Professor Koken,' and refer- 

 ence should l)e had to his writings by all interested in this subject. A 

 summai'v of tlie earlier litei'ature is given hy him in the fii'st paper cited 

 helow. Jf any are ineliut'd to ([uestion tlie accuracy of his determina- 

 tions of genera and species, the opportunity is certainly open for more 

 extended comparisons with recent and fossil forms. 



Otolites occnr rather freqnently in the Eocene of Maryland, l)Ut only 

 a few have been finind in the Miocene at Plum Point. A few typical 

 examples are shown in Plate XII, Figs. 4-6, but further than to say that 

 they bear a general resemblance to those of the Gadidae, tlieir identi- 

 fication is not attempted here. 



Occurrence. — iSrAXJE:\roY Formatiox. Port Tobacco, 2^ miles above 

 Popes Creek, Woodstock. 



Collect ion. — ^Maryland Geological Survey. 



COPROLITES. 

 Eolled cylindrical bodies of amorphons structnre and very suggestive 

 of fossil fish excrement are occasionally found at a few localities in the 

 Eocene of Maryland and Virginia. The occnrrence of coprolites of enor- 

 mons size in the Miocene of Virginia has been known for a long time." 



' Lor. rit., pp. .500-.56o. — Neue Untersucbungeu :m tertiiiren Fisch-OtolitbeD, ibhJ., 

 vol. xl, 1SS8, pp. 274-30.^. 



- Wvman, Notice of Remains of Vertebrated Animals found at Ricbmoud, Virginia, 

 Amer. Jour. Sci., ser. ii, vol. x, 1S50, p. 235. 



