. Science-gossip . rpentieri, , C. erronea, C. rivolii, C. odontophora, and The only other species of the genus atpresent known, are C. anax, Benson, and C. bed-domeae, Hanley. The two species last named, with which we arehere concerned, form a separate group in the genus,and, from considerations which will be explainedfurther on, may be looked upon as being the oldestmembers of the group provided with plates, Corillacharpentieri being the primordial form. This groupof Corilla anax (including C. beddomeae), is of equalvalue to the group of Corilla erronea (including ,
. Science-gossip . rpentieri, , C. erronea, C. rivolii, C. odontophora, and The only other species of the genus atpresent known, are C. anax, Benson, and C. bed-domeae, Hanley. The two species last named, with which we arehere concerned, form a separate group in the genus,and, from considerations which will be explainedfurther on, may be looked upon as being the oldestmembers of the group provided with plates, Corillacharpentieri being the primordial form. This groupof Corilla anax (including C. beddomeae), is of equalvalue to the group of Corilla erronea (including , C. rivolii, C. odontophora and C. humberti) andto the remaining group of Corilla charpentieri. Corilla anax is shown in figs. i2a-e, thedrawings having been made from a specimen inMr. Ponsonbys collection. It is the only speciesof Corilla known to occur outside Ceylon, beingfound, as already stated, in the southern part ofIndia. It is of a dark chocolate colour, andpossesses three parietal and four palatal Fig. 12.—Corilla anax Fig. 12a shows the entire shell, four of the plates,two parietal and two palatal, being visible fromthe aperture. The parietal plates are muchbroader than in the other species, No. i curvesupwards, while No. 2 reaches as far as theparietal callus; but, unlike those of the otherspecies, they are separate. No. 3 parietal plate isalmost horizontal, with but a slight curve, as willbe seen on reference to fig. 12c, the specimenbeing there figured with the outer wall i2d shows the same shell with part of theouter wall broken away, and the plates are shownas they appear from behind their inner termina-tions. The palatalplates also are seen tobe much broader thanin the other species, andthe three upper onesare much more oblique,resembling in this re-spect the immatureplates found by me inthree of the otherspecies. In fig. i2e aportion of the last whorlis drawn, in which thepalatal plates Nos. i, 2and 3 are shown asthey appear throughthe
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