168 PAGODULLNA. 



The following named forms are not known to me by speci- 

 mens: P. pagodula austeniana New., possibly a form of sub- 

 dola, but the internal structure is unknown. P. tchapecki 

 Gredl., possibly pathologic ; P. pagodula var. adaucta de Betta, 

 insufficiently defined. These several forms have not been 

 observed by any other authors since their description. 



Key to Species and Chief Varieties of Pagodulina. 



1 f Length 1.4 mm. P. bourguignati, no. 4. 



1 Length 3 mm. or more (2). 



Having a short lower-palatal fold below the long palatal 



fold within the ventral side of the last whorl (3). 

 No lower-palatal fold below the long one (5) . 



A suprapalatal fold above the long median one, 3 palatals 

 in all. P. subdola admnii, no. 2c. 



No suprapalatal fold, there being only two palatals (4). 



Shape and sculpture about as in P. pagodula, the riblets 

 being spaced, becoming close on the last half-whorl. 

 4 ^ P. subdola, no. 2. 



More slender, the riblets remaining well spaced on the 

 last half-whorl. P. subdola gracilis, no. 2d. 



Riblets rather widely spaced, 6 to 10 in 1 mm. on the 



face of penult whorl ; Europe (6) . 

 Riblets closely crowded throughout, about 15 in 1 mm. 



on face of penult whorl; Caucasus region. 



P. lederi, no. 3. 



f About 8i/> whorls, little more than the last one exposed 

 J in the closed, J-shaped umbilical cavity (7). 



10 whorls, 4 mm. long, the penult whorl exposed in the 

 round umbilicus. P. s. form tschapecki, no. 2a. 



f Riblets well spaced, becoming decidedly closer on the 

 J last half-whorl. P. pagodula, no. 1. 



I Riblets remaining well spaced on the last half-whorl. 



P. pagodida sparsa, no. 16. 



