292 LEPTAXIS. 



brown, banded or maculated. Whorls 5 to 6, the last wide, deflexed 

 in front. Aperture transverse-oval, oblique, the outer lip simple or 

 expanded, columella usually widened. Type H. erubescens Lowe. 

 (See pi. 43, fig. 41, L. undata; fig. 36, L. lowei; fig. 45, L. web- 

 biana). 



Jaw (pi. 67, fig. 20 L. undata) well arched, strong, bearing very 

 widely unequally separated linear riblets, converging below, forming 

 median triangle. 



Radula (pi. 67, fig. 19, L. undata) having the cusps of median 

 teeth about as long as basal plate, side-cusps obsolete; basal plate 

 with a backward-projecting tongue-like process. Lateral teeth with 

 a stout ectocone. Marginals having the inner cusp shorter than 

 usual and obtusely bifid, outer cusp simple. 



Genital system (Frontispiece, figs. 8, 9, L. undata) having the 

 penis continued in an epiphallus which bears the retractor and ends 

 in a short flagellum and the vas deferens. Dart sack large, seated 

 on atrium. Mucus glands in two clusters, one composed of 5, the 

 other of about 10 tubes, which adhere laterally by twos or form larger 

 palmate groups (fig. 8, d. s. turned downward and groups of 

 mucus glands spread). Spermatheca very large, rather boot-shaped, 

 with a basal ccecum embedded in uterus; duct long and without 

 diverticulum. The penis-retractor is inserted distally on the lung 

 floor, and the right eye-retractor passes between branches of genita- 

 lia. Dart of large size, a little curved, with a lateral expansion on 

 each side. Spermatheca contained a rod-like chitinous spermato- 

 phore, star-like in section. 



The jaw of L. undata is peculiar and unlike that of any allied 

 form, resembling most the jaw of Plectopylis. The teeth are char- 

 acterized by the strong development of ectocones on the inner 

 laterals. The genital system is remarkable for the unusual size and 

 shape of the Spermatheca which lacks diverticulum unless it be re- 

 presented by the basal sack figured. The mucus glands are in two 

 groups, and inserted on the vagina as usual in Helix, but the in- 

 dividual tubes adhere laterally in a way I have not observed in 

 other forms. They are not bound together like those of Eulota* 

 however. The dart had unfortunately been expelled from the in- 

 dividuals examined, but has been described by Morch (Journ. de 

 Conch. 1865, p. 390). 



I had expected to find in Leptaxis some archaic characters pre- 

 served ; for its geographic position and the shell-peculiarities argue 



