SPIBAXIS. 19 



-slender but otherwise exactly similar. Chitty's 8. contorta 

 was 'based upon a specimen of 8. anomalus. It measured 7.5 

 x 1.75 mm., with 10 whorls. 



Pfeiffer changed the name of Adams' species on account 

 of his own earlier Achatina anomala, which he transferred to 

 Spiraxis in 1853 ; but that species is a Leptinaria and was not 

 referred to Bulimus or Spiraxis until after the publication by 

 Adams of his B. anomalus. 



4a. S. (?) PARVULUS (Chitty). 



" Shell sub-cylindrical, whitish with a yellowish epidermis, 

 with strong transverse stria? on the last 5 whorls, becoming 

 obsolete on the lower extremity of the last whorl. The apex 

 quite free from strias. Spire with almost 'rectilinear outlines. 

 Apex very obtuse. Whorls 7, rather turretted; last whorl 

 much so. At one-half of the labrum the aperture is singu- 

 larly constricted, and there is a large opal white tooth, at the 

 point of constriction ; thence it is very abruptly truncated, 

 and the labrum thickened ; the columella is considerably thick- 

 ened; and is also of an opal white. Aperture very long, 

 much twisted and sub-angular above. Mean divergence about 

 12. Length .14, breadth .04, length of aperture .04, Habitat 



-? From Dr. Hyde." (Chitty). 



Achatina parvula CHITTY, Contrib. to Conch, no. 1, p. 14 

 (Oct., 1853). PFR., Monogr. iv, p. 618. 



A problematic Jamaican snail, known to me by the above 

 description only. 



Sub genus RAVENIA Crosse. 



Ravenia CROSSE, Journ. de Conchy!, xxi, 1873, p. 69 ; xxii, 

 1874, p. 67, for R. Uandi Crosse, t. c. p. 69, pi. 2, f . 4. 



This group has been included in Vol. I by Mr. Tryon, p. 52. 

 It seems to be very closely related to Euspiraxis, differing 

 only by the slightly thickened outer lip, which has a more 

 prominent angle in the middle, as seen in profile view, than 

 the Jamaican forms. The columellar lamella is not quite 

 so prominent. These differences 1 would not be thought of 

 much importance were it not for the remoteness of the local- 



