MOLLUSCA OF INDIA. 



101 



elongated simple form with no flagellum. All this arrangement 

 and proportiou of the parts to one another in the male organ differs 

 much from what is seen in Ilacrochlamys, and even in Ariophanta 

 and Nilgiria. The mncous pore is large (fig. 3), extending to the 

 sole of the foot, which is undivided. In this last respect there is 

 considerable modification of structure. 



EuPLECxA sEMiDECussAXA, Pfr. (Plate XCVII. figs. 2-2 d.) 



Helix semidecussata, Pfr. P. Z. S. 1851, p. 252 ; Kiist. ed. Chemn. 

 ii, no. 955, t. 145, figs. 8, 9 ; Pfr. Mon. Hel. vol. iii. p. 53 ; Reeve, 

 Conch. Icon. cii. fig. 567 (very good figure) ; Hanley, Conch. Ind. 

 p. 27, pi. Iviii. fig. 1 ; 0. Collett, Journ. R. Asiat. Soc. (Ceyl. Br.), 

 vol. XV. p. 3 (1897). 



Helix semidecussata, var. solida, Bs., Hanley, Conch. Ind. p. 27, 

 pi. Iviii. fig. 2. 



Hemiplecta semidecussata, Clessin, Nomen. Helic. 1881 , p. 50. 



Rotula (sec. A) semidecussata, Theob. Supp. Cat. p. 21 ; wrong 

 plate is quoted. 



Nanina semidecussata, Nevill, Hand-list, p. 29. 



Hab. Ambagamuwa, Ceylon (0. Collett). 



Evidently two different species are figured in the ' Conch. Indica,' 

 one with a raised keel belonging to the genus Euplecta, the other 

 has no sign of it. 



Nevill says, in his MS. copy of 'Hand-list,' there is a closely allied 

 species from Madagascar ; and Hanley says, essentially identical 

 with the Mauritian species. Whether the animal will prove to be 

 so is an interesting point to be ascertained. 



Original description : — " H. testa perforatd, conoided, solidd, 

 superne minute decussatd, opacd, unicolore rufo-fuscd ; spird conoided, 

 acatiusculd ; anfructihtis 7, vix convexiusculis, idtimo carinato, non 

 descendente, basi convexo ; apertura diagonali, angidato-Uumri ; 

 peristomate simplice, recto, obtuso, margine columellari superne 

 brevissime rejtexiuscido. 



"Diam. maj. 33, min. 30, alt. 18 mill. 

 " Hah. in insula Mauritii." 



Collett writes*:— "I have found this species fairly common 

 throughout the district. It occurs among fallen leaves in forest 

 and scrub, and is much preyed upon by birds, with whom it appears 

 to be a favourite food. I have occasionally come across a sacrificial 

 stone in the jungle surrounded by heaps of broken shells. When 

 alive, the animal, which is mottled black and white, gives a hand- 

 some ' checked ' appearance to the reddish-brown translucent shell. 

 The body-whorl of young specimens is acutely angular." 



This black and white motthng is not on the foot of the animal, 

 but on the integument covering the branchial chamber. 



The specimen now described was obtained on the Binoya Estate 

 {Collett). 



* Journ. Roy. As. Soc. (Ceylon Branch), vol. xv. : " Contributions to Ceylon 

 Malacology." 



