200 Zoological Society. 



Hub. Matnog, province of Albay, island of Luzon, Philippines 

 (found on the reefs) ; Cuming. 



Partaking as this shell does in almost equal proportion of the 

 characters of botli Triton and Ranella, it has been a matter of some 

 difficulty to decide to which of the two genera it might with the 

 greater propriety be referred. 



Triton exilis. Trit. testa clavaformi, varice unico parvo ; spird 

 breviuscidd ; anfractibus superne angxtlatis, inferne coarctatis, 

 transversim subirregnlariter costatis, costis liris parvis longitndi- 

 7mHbus deciissatis, tuberculatis, tubercitUs grandibus, prominenti- 

 bifs, subcompressis ,■ alba, aurantio-fusco sparsim tinctd ; columrUd 

 plica td, pi ids superioribus valde major ibus, apertura fauce albd, 

 labro intus nigoso-denticulato ; cunali longissimo, superne peculi- 

 ar iter contorto. 

 Conch. Icon., Triton, pi. 4. f. 11. 



Hab. San Nicolas, island of Zebu, Philippines (found in sandy mud 

 at the depth of ten fathoms) ; Cuming. 



This highly interesting species has been erroneously published by 

 Mr. Sowerby in his ' Genera of Shells,' and by myself in my ' Con- 

 chologia Systematica,' vol. ii. plate 243. fig. 3, for the Triton clavator, 

 and demonstrates how necessary is the examination of an entire 

 genus by comparison for the proper discrimination of the species. 

 No question as to the specific difference of these two shells could 

 however be urged, for they vary materially both in form and detail 

 of sculpture. The Triton clavator is comparatively full and ventri- 

 cose, with the upper ribs only moderately tubercled ; the Triton ex- 

 ilis is small, peculiarlj^ contracted round the lower part, with the 

 tubercles very prominently developed entirely across the whorls : in 

 the former species there is a varix on the penultimate whorl as well 

 as upon the last whorl ; in the latter species, as in the Triton cana- 

 Uferus, there is no varix upon the penultimate whorl ; lastly, the 

 mouth of the former species is either yellowish or yellowish scarlet, 

 whilst that of the latter exhibits not the slightest indication of colour, 

 and the stains of orange-brown with which it is marked externally 

 are of a character not to be misunderstood. 



Triton Pfeifferianus. Trit. testd fusiformi, varicibus septem 

 jyronnnentibus, acutangularibus ; spird elatd ; anfractibus subirre- 

 gulariter convolutis, convexis, superne piano -depressis, leviter 

 canaliculatis, transversim costulatis, costulis irregular ibus, 7iunc 

 angustis, nunc latioribus, striis elevatis longitudinalibus nodvloso- 

 decussatis, anfractuum parte mediand nodosa, nodis distantibus, 

 longitudinaliter subplicatis ; fuscescente, fusco pallide varid; colu- 

 melld rugulosd, labro intus riigoso-denticulato ; canali subelongato. 



Conch. Icon., Triton, pi. 4. f. 14. 



Reeve, Pro. Zool. Soc, 1844. 



Hab. ? 



This species may probably be recognised as one of not uncommon 

 occurrence, though not hitherto described ; its leading features are 

 the rude manner in which one whorl is deposited on the other, the 



