I"! Kill. OB I OROXK ER \N BRAXt II. 189 



Coronicoras Huimaruum H 



I ! pi \v 



The figure of tbia Bpecies \ the exacl form and characteristic of the 



It has similar unshapely genicular thrown out beyond the 

 - of the abdomen, giving tin- whorl a peculiar angular and squared aspect ; 

 reniculae also interrupt tin- channel ridges, ami the keel, though well de- 

 ed, i- almost counter-sunken in the deep channels. The pila? are very 

 in // id have no tubercles; the form i- what inure 



compressed than in I i are perfectly flat anil parallel, ami 



tin' depre 1 abdomen and nearly equally flattened dorsum are of tin- same 



breadth, the whorl in section being a parallelogram with the Bides about "in 1 

 fifth longer than the transverse diameter. The specimen figured by Hauer was 

 135mm. in diameter, and consequently the complete shell must have reached a 

 much •■ his specimens exhibil no signs of the approach of senility. 



Third Si bsi rii s 

 Coronicoras latum. Htatt. 



PlaM III Pit IS ■ ; ... -iimm. II. Ml lit. 111. 



Hyatt, Bull. Mo ' 77 



\ - Jura, pi. ix. 1 



' ;. — S<-llllir 



Many "f tin- young of thi- species, Plate 1 1 1 Fig 22, '_'•">. have large tubercles 

 early on the second whorl, and on the third these become elongated into tuber- 

 cular folds On the fourth, <>r mi the latter part "f the third volution, the inter- 

 en them increase, ami they become true pil®. In other specimens, 

 19, the pilsB are acquired a- in rottforme, Plate 111 Fig. 5, and there 

 • in many specimens, Plate 111 Fig '_"-'. a close resemblance t" tin' adult of 

 ' , Plate 111 The keel appears on the first quarter of the fourth 



whorl, l»ut at tl rved on the second quarter <>i the fifth volu- 



• keel was -till very thin. Bharp, and but slightly elevated. The 

 channels, however, th shallow and broad, bad acquired lateral i 



On the second whorl the breadth >>t the abdomen i» verj much increased by the 

 -. tin' -ides becoming exceedingly divergent in some 

 . and the abdomen gibbous On the fourth whorl the central area 

 i . 23, hut the abdomen on either side 



irrelation with this and « i th the i 

 entirely covered by the - whorls, 1 



1 ■ Plate III. 1 both 



e double : in others, the and the 



re double; on another, the duplication "t tl. 



•he fourth w borl, with ti 

 r. « hi< h 



