AUR1S. XV 



Subgenus AURIS s. str. 



The anatomy of A. bilabiata and A. egregia has been examined 

 by Semper. There is a rather broad and long mantle-lobe extending 

 along the whole left mantle-edge. The kidney is short, hardly longer 

 than the pericardium; secondary ureter closed. The venation of the 

 lung is confined to the neighborhood of the pneumostome. 



The genital system (pi. .50, fig. 13, A. egregia, after Semper) is 

 simple, the penis with terminal retractor and no papilla. At its 

 base there is a circular muscle, embracing also the vas deferens, 

 as in many Bulimulus. The small spermatheca is borne upon a 

 long duct. 



The jaw of bilabiata is composed of 13 unequal, broad, flat ribs, 

 hardly projecting below. In egregia there is a very wide, smooth- 

 edged median plait, with two broad ribs on each side, not produced 

 on the cutting edge. 



The radula has 61-63 teeth in bilabiata, 65-67 in egregia, the 

 transverse rows being slightly angular in the middle. The middle 

 tooth is tricuspid, median cusp wide ; the laterals have a small 

 ectocone and obtuse mesocone. 



The jaw in this group is in a transition state from the plaited to 

 the smooth type. The genitalia and teeth offer no differences of im- 

 portance from those of Eudolichotis. 



A. bilabiata B. & S., x, 99. A. icterostoma Mart., xiv, 132. 



Helix maximiliana Fer. A. chrysostoma Mor., x, 103. 



var. melanostoma Mor., x, var. swainsoni Pfr., x, 104. 



101. A. bernardii Pfr., x, 105. 



A. egregia Jay, x, 101. A. illheocola Mor., x, 106. 



var. nigrilabris Pils., x, 102. 

 A. melastoma Sw., x, 102. 



B. melanostomus Dh. 



B. struthiolaris Mke. 

 var. brachyplax Pils., x, 103. 



Subgenus (?) OTOSTOMUS Beck, 1837. 

 Manual, x, p. 107. 



The apex in this group is exactly like that of Drymseus and of the 

 sections of Odontostomus grouping around the typical subgenus. 

 Whether the group belongs to Auris, or is a distinct genus near the 



