COEILLA. 61 



C. erronea ; the last whorl, however, more descending and more 

 contracted at the spot where the lamellae show most conspicuously 

 through the shell. Sculpture nearly as strongly marked on the 

 lower as on the upper surface ; C. gudci differin,^ thereby from 

 all other known Ceylon forms akin to it and recalling the Indian 

 C. ancLV. Outer lip slightly more refiexed than in C\ erronea ; the 

 mouth not so drawn out and slightly more rounded. Palatal and 

 parietal lamelite the same in number as in C. erronea, but somewhat 

 shorter ; differing also in situation by being more nearly parallel, 

 especially (counting from above) the second and third palatal 

 ones. Umbilical area more impi'essed in the present species. 

 Colour a little lighter than in C. erronea ; a few specimens have a 

 rosy tint. 



" Long. 23-22, lat. 16-17, alt. 7-6-5 mm." (S>/l-es.) 



Hah. Ceylon : Karunegala (Collett). 



"As compared with C. anacc, the present species differs in 

 having one whorl more, the whorls being more flattened above, 

 the lip more reflected, and the last whorl not so inflated or 

 pi'oduced." (Syl-es.) 



In addition to the differentiating features referred to by 

 Mr. Sykes, C. r/iidei, in spite of the fact that it possesses nearly a 

 whole whorl more than C. anax, is about 5 mm. shorter in 

 its major diameter, the ribs are a little coarser and more widely 

 spaced, and the mouth is much less dilated transversely. The 

 second and third palatal lamellie, moreover, are much less oblique 

 and nearer the aperture. 



A number of immature shells of various sizes, received from 

 the late 0. Collett, possess the immature barriers, similar to those 

 observed by me in all the other species of Corilla. One specimen 

 has nearly three whorls completed and is provided with the usual 

 five palatal lamellte about one-quarter of a whorl beyond the post- 

 embryonic whorl. 



71. Corilla humberti, Brot. 



Helix humberti, Brot, Journ. Conelivl. xii, 1864, p. 21, pi. 2, fi<>s. 5, 

 6 ; Hanley & Theobald, Conch, liad. 1876, pi. 159, tig. 9. 



Helix (Corilla) htimberti, Nevill, Hand List, i, 1878, p. 70. 



Helix (Atopa) humberti, Tryou, Man. Conch, ser. 2, iii, 1887, p. 156, 

 pi. 33, figs. 22, 23. 



Corilla humberti, Pilsbry, Man. Conch, ser. 2, ix, 1894, p. 148 ; 

 Gude, Science Gossip, N. s. iii, 1896, p. 92, fig. 11 (shell and 

 armature) ; Pilsbrv, Proc. Malac. Soc. London, vi, 1905, p. 288, 

 lA. 13, figs. 1-3, pi. 14, figs. 10-12 (anatomy). 



Original description : — " T. late et profunde umbilicata, dis- 

 coidea, subirregularis, solidula, superne costulato-striata, subtus 

 vix striatula, nitida, unicolor olivaceo-fusca ; spira plana. Anfr. 5 

 vix convexiusculi, ultimus antice descendens. Apertura obliqua, 

 obtuse cordata, lamella una parietali, central!, valida, sinuata et 

 palatali una profunda, brevi (extus baud conspicua) coarctata. 



