EUPLEOTA. 53 



The shell differs, as a rule, fron that of Arioplwnta by havin<^ 

 more whorls and being more closely wound, but there are 

 exceptions. Most of the species are carinate. 



Animal externally much like Arioplianta. A large mucous pore 

 at the posterior extremity o£ the foot, sometimes with a small 

 lobe above it. 8heli-lobes generally wanting, the riglit sometimes 

 present in a minute or rudimentary form ; dorsal lobes moderate 

 in size, the left in two parts. The sole' indistinctly folded in the 

 middle when contracted. 



In the genitalia the most important character to distinguish 

 this genus from Ariophanta is the presence of a muscular band, 

 given off from the retractor muscle and holding part of the penis 

 doubled into a loop. Apart from this looped arrangement, the 

 male organ is elongate and .simple, with the retractor muscle 

 attached to a longer or shorter straight caecum as in Ariophanta. 

 Amatorial oi'gan and other appendages as in Arioplianta. JSperraa- 

 theca very short. Vas deferens leading to junction of kale-sac and 

 epiphallus. Spermatophore as in Arioplianta. 



Kidney short, Radula [out of 11 species examined, 9 have 

 the admedian band of teeth a little more than half as wide as in 

 Arioplianta, in proportion o£ 28 : 42 respectively]. Jaw with or 

 without median projection. 



[Before commencing the list of species in the genus Euplecta, it 

 becomes necessary to refer to the position of one of ISemper's 

 types, viz. E. layardi, Pfr., to avoid possible confusion in the 

 future. Dr. W. T. Blanford in his MS, makes Helix baconi from 

 Moradabad, subdecussata from Bombay, and layardi from Ceylon 

 one and the same species — figuring the shell of layardi under the 

 name of baconi, this name of Benson's having priority. The very 

 little we know of Helix baconi does not bear out this conclusion, 

 and I am constrained to keep all three species separate, for reasons 

 given further on, as well as our knowing nothing of the animal 

 of true H. baconi from Moradabad nor of subdecussata from 

 Bombay. Blanford's MS. is as follows under no. 81, Euplecta 

 baconi = layardi.'} 



An examination of the type of Benson's Helix baconi has shown 

 that it is an immature shell of H. subdecussata, Pfr., which is the 

 Indian form of the Ceylonese H. layardi. H. convexiuscula is a 

 small form of the same species. Pfeiffer's original description of 

 H. layardi was also taken from an immature shell. 



Large specimens fx*om Ceylon measure as much as 18 mm. in 

 major diameter ; small shells from Orissa only 12. 



K subdecussata (or rather E. baconi), the Indian form but also 

 occurring iia Ceylon, is rather more closely wound than the 

 Ceylonese E. layardi, but there is variation in this respect. The 

 two, however, may be regai'ded as races or subspecies. 



Specimens from Baticaloa and Hambantote on the east coast of 

 Ceylon are fulvous horny. 



The whorls of E. baconi were said in the original description to 

 be bordered by a narrow dark rufous baud. This cannot now 

 be detected. 



