164 HELICID^E. 



] 36. Planispira trochalia, Benson. 



Helix trochalia, Benson, A. M. N. II. ser. 3, vii, 1861, p. 82 ; 



Hanley & Theobald, Conch. Ind. 1870, pi. 28, fig. 7 ; Stoliczka, 



Proc. A. S. B. 1870, p. 87 ; Pilsbiy, Man. Conch, ser. 2, vii, 1891. 



p. 88, pi. 18, figs. 67, 68. 

 Ampdita (Helix) bigsbyi, Tryon, Amer. Journ. Conch, v, 1869, 



p. 110, pi. 10, fig. 3. 



Helix (Planispira) trochalia, Nevill, Hand List, i, 1878, p. 77. 

 Planispira (Trachia) trochalia , Pilsbiy, Man. Conch, ser. 2, ix, 



1894, pp. 115, 116, pi. 34, figs. 4, 5 (jaw and radula). 

 Planispira trochalia, Godwin-Austen, P. Z. S. 1895, p. 442. 



Original description : " H. testa anguste umbilicata, solidius- 

 cula, orbiculato-conoidea, subtrochiformi, irregulariter arcuato- 

 striatula, striis nonnullis prominentioribus, castanea, apicem versus 

 albida ; spira conoidea, apice valde obtuso, sutura leviter impressa ; 

 anfractibus 5, primis convexiusculis, cseteris planiusculis, ultimo 

 acute eompresso-carinato, antice breviter descendente, subtus 

 convexo ; apertura obliqua, elliptico-lunata ; peristomate tenui, 

 undique expanse concolori, marginibus subconniventibus, colu- 

 mellari dilatato, umbilicum profundum seinitegente." (Benson.) 



Diam. maj. 17'5-23'5, min. 15-5-20-5, alt. 12-15 mill. 



Hob. Andaman Islands : Port Blair (Ifaughton). 



A peculiar form readily recognized by its trochoid spire. No 

 reference is made in the description to the fact that the last whorl 

 is suddenly contracted behind the peristome, nor to the presence 

 of a hydrophanous cuticle. The shell, moreover, is covered above 

 and below except at the protoconch, which is smooth and 

 shining with excessively minute and densely crowded, wavy, 

 spiral lines ; the base has in addition a few distant spirals. In 

 colour the species varies from, pale fuscous to chestnut. Godwin- 

 Austen mentions a variety, conico-elata one of Nevill's MS. 

 names but gives no definition. 



137. Planispira vittata, Mutter. 



Helix vittata, Miiller, Verm. terr. fluv. ii, 1774, p. 76; Wood, 

 Index Test. 1825, pi. 34, fig. 93 ; Orbigny, Diet. Hist. Nat. Atlas, 

 iii, 1849, pi. 19, figs. 3, 4 ; Deshayes in Ferussac, Hist. Nat. Moll, 

 i, 1850, p. 233; Chenu, Illustr. Conchyl., Helix, 1851, pi. 10, 

 figs. 6, 7 ; Reeve, Conch. Icon, vii, 1852, pi. 78, fig. 412 ; Pfeiffer, 

 Conch.-Cab., Helix, i, 1853, p. 329, pi. 58, figs. 15, 16, 18, 19 ; 

 Hanley & Theobald, Conch. Ind. 1875, pi. 130, fig. 10 ; Kobelt, 

 Illustr. Conch. Buch, ii, 1879, pi. 73, fig. 21. 



Helix (Helicoffena) vittata, Femssac, Hist. Nat. Moll. 1822, pi. 25 A, 

 fig. 9, pi. 26, figs. 4-6. 



Helix spinolce, Villa, Disp. Syst. Conch. 1841, p. 55. 



Helix zonula, Wood, Index Test, Suppl. 1828, pi. 7, fig. 8. 



Helix (Planispira) vittata, Nevill, Hand List, i, 1878, p. 76. 



Helix (Eurystoma) vittata, Albers, Die Helic. 1850, p. 126 ; Tryon, 

 Struct. Conch, iii, 1884, p. 40, pi. 95, fig. 58; Tryon, Man. 

 Conch, ser. 2, iv, 1888, p. 120, pi. 33, figs. 59, 60, 62 ;' Godwin- 



