10 PSEUDOSUBULINA. 



Cuba: Matanzas (Pfr., type loc.) ; Managua (Poey) ; 

 Rangel (Arango). Under dead leaves. 



Achatina exilis PFR., Archiv f. Naturg. 1839, i, p. 352; 

 Monogr. id, 268. Subulina e., ARANGO, Fauna Malac. Cubana, 

 p. 99. CROSSE, J. de C. 1890, p. 248. Achatina michaudiana 

 ORB., in Sagra's Historia etc., Moluscos, p. 90, pi. 11 bis, f. 7, 

 8, 9 (erroneously marked A. consobrina at foot of plate). 



The specimen figured measures 4.5 x 1.1 mm., with 7% 

 whorls, being the largest of five before me. The summit is 

 obtuse; first half whorl smooth, very delicate striae then be- 

 ginning. These increase in size gradually upon the narrow, 

 attenuate portion of the shell, and more rapidly where the 

 diameter begins to increase. The later whorls might better 

 be described as grooved rather than as rib-striate. The 

 grooves are slightly arcuate and very much narrower than 

 their flat intervals. They become weaker or subobsolete on 

 the base of the last whorl. The columella is concave above, 

 and subvertically truncate basally. 



Figure 62 of plate 44, vol. XVIII, represents the synonym- 

 ous A. michaudiana of Orbigny. In the Historia, Orbigny's 

 references to the illustrations of A. consobrina and micliaud- 

 iana were transposed, both dn the text and in the legend at 

 foot of the plate. The error was repeated in the later French 

 edition. 



The systematic position of this species is not certain. 



P. exilis has a superficial resemblance to Spiraxis melaniel- 

 loides, but the columella is of quite different shape. It is a 

 Subulinoid species, not unlike the lengthened Antillean Lepti- 

 narias. I have been in doubt as to its real position, which can 

 only be demonstrated by study of the soft parts. It does not 

 seem referable to Varicella, though having some characters of 

 the section Varicellula. 



17. P. ( ?) PROBLEMATICA Pilsbry, n. n. PI. 20, figs. 2, 3. 



The shell is minute, imperforate, pure white, slender, and 

 tapers slowly to the obtuse summit. The first whorl is smooth, 

 riblets beginning on the second. The later whorls are rib- 

 striate, the riblets not more than half as wide as the smooth 



