488 MESSRS. ADAMS AND ANGAS ON NEW LAND-SHELLS. [June 6, 



sile organ in a very subordinate manner only. This defect is com- 

 pensated by the development of an additional sharp denticle at the 

 inner base of each claw, and of a spine vertically projecting from the 

 flexor side of each finger and toe, which must immensely strengthen 

 the power of the animal for holding on to branches, &c." * 



The posterior extremities are short, the legs very short and thick ; 

 and the outer and inner toes are shorter and much thicker than the 

 others, as in Nyctinomus ; but they are not fringed with long hairs. 

 The feet are remarkably large, and much rotated outwards and for- 

 wards, so as to allow of easy progression. The structure of the sole 

 of the foot and of the inferior surface of the leg is very peculiar, and 

 is well shown in the accompanying woodcut (fig. b). The plantar 

 surface, including the toes, is covered with soft and very lax integu- 

 ment, deeply wrinkled ; and each toe is marked by a central longitu- 

 dinal groove with short grooves at right angles to it, as in the genus 

 Hemidactylus (Geckotidee). The lax wrinkled integument covering 

 the sole of the foot is continued along the inferior flattened surface 

 of the ankle and leg. 



All these peculiarities of structure must accompany some corre- 

 sponding peculiarities in the habits of this species. As the denticle 

 at the base of the claw in Rampholeon spectrum evidently compen- 

 sates that animal for the shortness of its tail, which is so effective a 

 prehensile organ in other Chameleons, so I have no doubt the den- 

 ticle at the base of the claw in Mystacina tuberculata compensates 

 that species exceptionally for the imperfect condition of the fore 

 limbs as organs of prehension ; and this, taken into consideration 

 with the peculiar manner in which the wings are protected from in- 

 jury when not employed in flying, and with the manifestly adhesive 

 nature of the sole of the foot and inferior surface of the legs, lead 

 me to believe that this species hunts for its insect food, not only in 

 the air, but also on the branches and leaves of trees, among which its 

 peculiarities of structure most probably enable it to walk about with 

 security and ease. 



6. Descriptions of five new Species of Land- Shells from 

 Madagascar, New Guinea, Central Australia, and the 

 Solomon Islands. By Henry Adams, F.L.S., and 

 George French Angas, C.M.Z.S. & F.L.S. 



[Keceived May 29, 1876.] 



(Plate XLVII.) 



Helix malantensis, n. sp. (Plate XLVII. figs. 1, 2, 3.) 

 Shell imperforate, trochiform, rather solid, faintly obliquely stri- 

 ated, whitish, ornamented with several broad or narrow fulvous or 

 dark chestnut bands, brown at the base; spire turbinate; whorls 

 * P. Z. S. 1871, p. li;j, with a woodcut 



