210 Panama Shells. AUKICULID^:. 



upper part of the lower whorls compressed ; last whorl sub- 

 angular next below the compressed part : aperture rather long, 

 very acute above : labrum moderately thickened but not reflected : 

 with three plaits on the left side, of which the middle one is 

 larger and the lower one is the least ; sometimes with a small 

 toothlike plait on the right side. 



The general form varies, as will be seen in the following 

 dimensions of two' specimens, the first number expressing the 

 mean divergence, the second the length, the third the breadth, 

 and the fourth the length of the spire : 



50 ; .44 inch ; .17 inch ; .23 inch. 

 65; .37 " ; .2 " ; .13 " 



Station. Under stones, at high water mark ; or crawling 

 over wet stones. 



Habitat. Panama and Taboga ; C. B. A. ! 

 650 specimens were collected near the sea wall of Panama, 

 where the species was most abundant. 



313. Auricula f agnails. 



Synonymy. 



Auricula stagnalis Orb. in Guerin Mag. Zool. Synop. 



p. 23.* July 1835. 



ReeveConcli.Syst.pl. 187. f. 9. (too narrow.) 1842. 



Orb. Voy. Am. Mer. p. 325. pi. 42. f. 7, 8. 1846. 



papillifera Kust. p. 25. ) _ 



7- TZ-.. >m r p'- 3 - f - 9 > 1. 10 



stagnalis Kust. p. 70. ) J 



Station. In a marsh, and even in stagnant fresh water ; M. 

 Fontaine ! Orbigny. 



Our specimens were found under a heap of stones just above 

 high water mark. 



* The vol. of the Mag. is not paged continuously, nor are the new species of 

 Mollusca, which are described by D'Orbigny, enumerated in the Table Methodique. 

 Kiister appears to be in error when he ascribes the authorship of this article to 

 M. Petit 



