HELIX. 323 



Shell depressed-globose, imperforate, solid, somewhat cretaceous ; 

 white, unicolored or banded, a five-banded pattern usually trace- 

 able. Surface usually finely malleated. Last whorl rounded at 

 periphery, deeply deflexed in front. Aperture very oblique, trun- 

 cate-oval, the outer lip expanded and thickened within, baso- 

 columellar lip straightened, reflexed and adnate, widened by an 

 internal callus. Type H. lactea Mull., pi. 44, fig. 11 (see also pi. 44, 

 figs. 9, 10, H. vermiculatci). 



Animal externally like Tachea. 



Jaw arcuate with blunt ends and 4 to 7 strong, convex ribs den- 

 tating both margins (pi. 67, fig. 4, H. vermiculata). Radula similar 

 to that of Tachea, side cusps being developed in some species, absent 

 in others (pi. 67, fig. 5, H. vermiculata). 



Genitalia (pi. 63, fig. 8, H. vermiculata*) similar to Tachea, but in 

 the typical species the mucus glands are split into a great number 

 of cseca, as in Pomatia. Dart coronated at base, with four blades, 

 which may be either simple (H. alonensis, pi. 63, fig. 13) or divided 

 (H. vermiculata, pi. 63, fig. 5). In the group of H.alonensis, balear- 

 ica, minoricensis, etc., the mucus glands have few fingers, as in H. 

 ( Tachea) nemoralis. 



Distribution, southern Europe, Northern Africa, Canary Islands. 



This section differs from Tachea in the more compact, solid shell 

 with generally a more deflexed last whorl and irregular color- 

 pattern. It presents no constant anatomical difference from Tachea, 

 but in most species the fingers of the mucus glands are more numer- 

 ous. 



The name Otala was proposed for three species, placed in two 

 sections. Section a contained hcemastoma (which, being the type of 

 a prior genus, must be eliminated, see ant. p. 153), and atomaria, a 

 new name for lactea Mull. Section b contained the Helix sulcata of 

 Miiller, a form which Swainson, in 1840, made the type of his group 

 Plicadomus. These eliminations leave H. lactea the valid nucleus of 

 Schumacher's group, and this name should have been adopted by 

 Albers in 1850; but, instead, he coined a new one Archelix. This 

 name was dropped in Marten's edition of Die Heliceen, 1860, and 

 the species placed in Macularia, a group originally proposed by 

 Albers for the spotted and unkeeled Iberus, and which did not 

 originally contain the species vermiculata, which Martens names as 

 its type! As the the type of Macularia had been expressly said to 



