DESCRIPTION OF NINE NEW SPECIES OF HELICOID 



LAND SHELLS. 



By G. K. GUDE, V.Z.S. 

 (Plates iii & iv.) 



When the first portion of I )r. J. C. Cox's collection of Shells came under 

 the hammer last year, Mr. E. R. Syk^s acquired inJer alia about 50 boxes 

 of small Helicoids (mostly from Polynesia) which he kindly entrusted to me 

 for examination. The majority pertain to known species, but six appear to 

 t)e undescriltcd, and another undescribed species was found, with a number 

 of Iki'fixU'.-: hriliudli, acquircd by myself from the same source. 



T a\ail myself of the opportunity afforded l)y the publication of descrip- 

 tions of these new species to describe also (1) a (V^/o/vV/n from Aru, of which 

 a single specimen was recently sent to me 1)\ Miss Lintcr tor identification, 

 and which differs from any species as )'et known : and (2) a new Plertotropis 

 from Java receiyed from Mr. (lerrard.- Mfn"eo\t'r, two species of (Jafhaira. 

 described b\- me in this join-nal (ynl. xi, p. 93) are likewise figured. A\'hen 

 describing these species 1 unfortunately oyerlooked the fact that one of them 

 (0. sfuraiit/i) had already been published by Dr. Kobelt in Rossmaessler 

 Iconographie, New Series (1S93), ^T. p. 75, \)\- 169, fig. 10S6. 

 Sitala pudica, n sp. 

 PI. iii, figs. 3a — 3b. 

 .Shell perforate, conoid, smooth a little shining, ])ellucid, thin, corneous ; 

 spire convex, suture impressed, apex obtuse ; whorls 4, a little convex, 

 increasing slowly ; last whoil not descending in front, angulated at the 

 periphery, tumid below. Aperture scarcely oblique, roundly lunate ; peristome 

 thin, straight, acute ; margins distant, columellar margin slightly dilated and 

 overhanging the narrow perforation of the umbilicus. 



Diam. 2 millim. ; alt. 1.5. 



Hah. — Cape Bvron, Byron Bay, New South Wales. 



Type in Mr. -Sykes' collection. 



Allied to 'Sitala suIiJinu's, Hedley, which, however is more rounded at the 

 periphery. It alscj resembles S. sfarlri, Brug., but that species is more 

 sculptured above. Several shells were found to contain a number of voung. 



Thalassia eookensis, n. sp. 



PI. iii, figs. 4a — 4b. 

 Shell umbilicated, conoid, finely striated, smoother and shining below, pellucid, 

 pale corneous, spire depr.^ssed, suture margined, apex obtuse. AMiorls 5, 

 convex, increasing slowly, last whorl not descending in front, slightl) flattened 

 l)elow, roundc-d at the perii)hery. Aperture oblique, semilunate ; peristome 

 thin, straight, acute ; margins approaching, u])[)er and outer arcuate, colum- 

 ellar ascending, slightly dilated o\er llu' moderate umbilicus. 



Diam. 4.5 millim. ; alt. 2.5. 



Hah. — Aitutake, Cooks Islands. (Garrett). 



Type in Mr. Sykes' collection. 



